December 31, 2010

8:00am Start Time for January 1st, 2011

STEVENS PASS MOUNTAIN WEATHER

12/31/2010 Weather

24HR SNAPSHOT starting NOON today

Water - 0 Snow - 0
Freezing levels -  500 - 1000'
Winds- 0-10 E

General Discussion: High pressure over the PNW will dominate the weather pattern for the remainder of the weekend.

Long-term: Long range models show signs of the high pressure breaking down sometime during the middle of next week. Therefore, dry conditions will continue until then.


TRENDS AND TIMING

Precipitation: 0

Freezing levels: Another cool night before temperatures starts to rebound on Sunday.

Winds: East flow will continue through tomorrow night.

December 30, 2010

Start Time Friday---8:00am

STEVENS PASS MOUNTAIN WEATHER

12/30/2010 Weather


24HR SNAP SHOT starting at NOON today

Water 0
Freezing Levels -  500'  rising 1000'
Winds - 0-10 E

General Discussion: An impressive convergence showing yesterday – got to love 6” of 3% snow with sunshine. This beautiful day will continue with cool temperatures and partly sunny skies.

Long-term: Building pressure over the PNW will create a split flow pattern, which in turn will bring beautiful weather to the mountains through the weekend. Warm air will begin to move in on Saturday.

TRENDS AND TIMING
Precipitation: 0

Freezing levels: Clearing skies will allow surface temps to drop into the single digits for the next few nights. Freezing levels will begin to rise on Saturday as warm air moves in from the south.

Winds: East flow will strengthen today.

December 29, 2010

Start Time Thursday---8:00am

Up coming training January 3rd-15th, Avalanche Control/Forecasting/Rescue.
Refere to comments for outline.

ICE AGE / GOOD TOURING

Dry cool conditions could make for some good backcountry travel.  Don't forget your sunglasses.

Building high pressure off the west coast
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STEVENS PASS MOUNTAIN WEATHER

12/29/2010 Weather


24HR SNAPSHOT starting at NOON today

Water - .10  Snow - trace
Freezing levels - 500'
Winds - 5-15 NW shifting NNE

General Discussion: Clearing and drying will start today as the atmosphere stabilizes under building pressure. Cold air from the north will also settle into the eastern basin for some pretty chilly low temperatures.

Long-term: High pressure will provide dry and cool conditions for the PNW through the weekend.

TRENDS AND TIMING
Precipitation: These convergence snow showers will taper off today with dry conditions developing this afternoon.

Freezing levels: Snow at SeaTac this morning must mean freezing levels are close to sea level. Clearing skies with cool air from the north will produce surface temperature in the single digits, or lower, for the next few days.

Winds: Gusty NW winds will begin to taper off tonight. Winds will shift N over night and eventually settle on easterly flow late tomorrow evening.

December 28, 2010

STEVENS PASS MOUNTAIN WEATHER

12/28/2010 Weather


24HR SNAPSHOT starting at NOON today

Water - .25  Snow 1-3
Freezing levels -  4500'  dropping to 1000'
Winds - 0-15 NNW

General Discussion: Last night’s storm tracked just south of the Pass which allowed us to avoid much of the rain. A cold front passing through today will bring lowering temperatures and light snow showers.

Long-term: High pressure off the California coast will build north during the next few days. This will most likely bring dry and cool weather to the PNW for the extended period.   Could be some good backcountry touring to bring in the new year.

TRENDS AND TIMING
Precipitation: Light snow showers will linger over the crest through noon tomorrow. A dry period will begin tomorrow afternoon and last through the rest of the week.

Freezing levels: Freezing levels will drop today and remain low through the next few days. Clearing and cool air streaming in from the north, could bring surface temperatures in the low teens or lower in the next few days.

Winds: Telemetry show some gusty ridge top winds still around. Winds should taper tonight and shift NNW. East flow will eventually develop by the end of the

Start Time Wednesday---8:00am

December 27, 2010

Start Time Tuesday 28th---6:15am

STEVENS PASS MOUNTAIN WEATHER

12/27/2010 Weather

24HR SNAPSHOT starting at NOON today

Water - .5 -.75  Snow - 6-8
Freezing levels - 3000' rising 5000' falling to 3k
Winds - 5-15 W gusty


General Discussion: A warm front will push moderate to heavy moisture into the Cascades tonight. This storm will quickly move east tomorrow with cool air and light snow showers following in its footsteps.

Long-term: Snow showers are expected to continue through Wednesday. Cool and dry weather is taking shape for the weekend.


TRENDS AND TIMING
Precipitation: Snow will today and become heavy tonight. A short lived rain and or mixed rain and snow event will be possible below 5000’ during the early morning hours. Precipitation will taper off after 4am tomorrow morning.

Freezing levels: Freezing levels will spike up to 5000’ after midnight tonight. The temperatures will quickly fall tomorrow as cooler air moves in.

Winds: A brief period of east flow will develop this afternoon but it will be quickly taken over by SW then W winds. Strong westerly winds are expected to accompany the front so expect gusty condition for the start of your day tomorrow.

December 26, 2010

8:00 am Start time for Mon. Dec. 27th, 2010

Should see a nice storm starting tommorrow!

December 25, 2010

8:00am Start Time for Dec. 26th, 2010.

Snow is coming!!!

STEVENS PASS MOUNTAIN WEATHER

12/25/2010 Weather


24HR SNAPSHOT starting at NOON today

Water - .25 Snow - 2-4
Freezing Levels -  4000'  dropping to 3000'
Winds - 0-10 E shifting W

General Discussion: A gift of powder on Christmas day, very nice. An approaching cold front will bring more moisture to the mountains tonight and tomorrow.

Long-term: A more westerly flow pattern is expected to develop over the weekend. This will produce a more active weather pattern to cap off the weekend and end the year.

TRENDS AND TIMING
Precipitation: Today will be mainly dry with snow developing later tonight. Light snow will fall through the following 24hrs.

Freezing levels: Freezing levels will hover near pass level today. Temperatures will begin to drop in the wake of the cold front, which is expected to pass through later today. Freezing levels will fall to or below 2000’ by tomorrow evening.

Winds: East flow will continue until early tomorrow morning. Westerly flow will fill in behind the cold front tomorrow. Gusty frontal winds will be possible tomorrow.

December 24, 2010

8:00 am Start Time for Christmas day, 2010.

Looks like we will start to get some snow!!!!

STEVENS PASS MOUNTAIN WEATHER

12/24/2010 Weather


24HR SNAPSHOT starting at NOON today

Water - .25 -.5 Snow 4-6
Freezing levels - 3000' rising to 4500'
Winds - 0-15 E

General Discussion: Last night’s storm stalled off the coast which has delayed the moisture until today.

Long-term: The pattern is slowly changing to a WNW flow. This should allow more systems to track towards the PNW for the remainder of the year.

TRENDS AND TIMING
Precipitation: Snow should arrive today and fall through the night. It will be possible to have a little rain snow mix in the base area, but it should be short lived, if at all.

Freezing levels: Freezing levels will rise to 4000’and possible 4500’ tonight. East flow will keep surface temps near or below freezing. Cooler air will arrive on Sunday.

Winds: East flow will continue through the next 24-36hrs.

December 23, 2010

What?

NW flow next week? Maybe.

 Long range 500mb vorticity models show strong NW flow aloft staring next week.  It will be interesting to see what this brings. Part of the pattern change discussed earlier.
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Start Time Friday---8:00am

STEVENS PASS MOUNTAIN WEATHER

12/23/2010 Weather

24HR SNAPSHOT starting at NOON today

Water - .25 -.5  Snow - 4-6
Freezing levels - 3500'
Wind - 0-10 E


General Discussion: A low pressure system in the Gulf of Alaska will slowly make its way south today. This will provide a more consistent moisture stream than the previous few days, although it will continue be showery.

Long-term: The jet stream is expected to lift north during the next few days. This will allow more organized systems to make their way to the mountains during the next 4-6 days.

An impressive showing at Mammoth California last week – record snowfall of 15.5 feet (186”) in 3 days.

TRENDS AND TIMING
Precipitation: Most of the snow should fall today. Tonight will be mainly dry before the next wave of moisture arrives during the day tomorrow.

Freezing levels: 4000’ freezing levels will bump up against the western slope as cool air from east continue to push through. Pass level surface temperatures will continue to be just below freezing for the next few days. Got to love that east flow.

Winds: Periods of some gusty east winds will be possible during the early morning hours but nothing significant.

December 22, 2010

Start Time Thursday---8:00am

Change is in the air

High pressuer centered over the intercontinental mountains is weakening.  This, along with a shifting jet streak, will start a more westerly flow over the PNW. 

Jet forecast for early next week.  Lifting north and flattening.
Animation of Jet Stream Forecasts

STEVENS PASS MOUNTAIN WEATHER

12/22/2010 Weather


24HR SNAP SHOT starting at NOON today

Water -.25 Snow 2-4
Freezing levels - 3000' steady
Winds - 0-10 E

General Discussion: It was nice to get a few inches of snow this morning to freshen things up. We can expect periods of light snow for the rest of the day.

Long-term: The pattern is slowly beginning to change. A series of weak fronts will begin pushing their way inland tomorrow. The weekend is looking good for some fresh snow. Stay tuned for details.


TRENDS AND TIMING
Precipitation: Light snow showers will continue today. Snow will ramp up a bit during the day tomorrow.

Freezing levels: Freezing levels will hover near the 3000’ for the next 24hrs. Cool surface temperatures will continue to be influenced by cool NE air.

Winds: East flow will weaken today and then re-strengthen tomorrow.

December 21, 2010

Start Time Wednesday---8:00am

Stuck in the Pattern

The jet continues to drive south. Northern Cali. and Oregon getting pounded.  Signs of it shifting north are in the models.

Jet forecast for next 24 hours. 
Animation of Jet Stream Forecasts

Jet model forecast for Saturday. 
Animation of Jet Stream Forecasts

STEVENS PASS MOUNTAIN WEATHER

12/21/2010 Weather


24HR SNAP SHOT starting at NOON today

Water - 25  Snow 2-4
Freezing levels -  2000' rising 3000'
WInd - 5-15 E


General Discussion: A low pressure cell spinning in the Gulf of Alaska will continue to spin bands of light moisture through the PNW today.

Long-term: We will be stuck in this showery pattern through the remainder of the week.

TRENDS AND TIMING
Precipitation: Light snow will continue today. A few inches of snow will be possible tomorrow morning as a moderate band of moisture passes through.

Freezing levels: Freezing levels will slowly rise to 3000-3500’ by mid day tomorrow. Cool air, NE of the crest, will help keep surface temperatures in the mid to upper 20s.

Winds: East flow will stay well established through most of the week.

December 20, 2010

Start Time Tuesday---8:00am

Over the next couple of storm cycles we will be shooting a variety of handcharges. Some emulsions w/cap wells and then 2 by 16 Nitro and then back to emulsions with no cap well which we will punch. We are now shooting the new AVR-2 at the C-7 Launcher--need weather vis over the next couple of weeks to site in. In the Bump Bibles you should find the MSDS on the products.

Jon

December 19, 2010

8:00 am Start Time for Mon., Dec. 20th, 2010

Keep thinking snow!!!

STEVENS PASS MOUNTAIN WEATHER

24HR SNAP SHOT starting at NOON today

Water - .24  Snow - 2-4
Freezing levels -  2000' -3000'
Winds - 0-10 E

Catching a few days off - The next discussion will be on Tuesday.  

Basically the same pattern of passing snow showers will continue into next week.

December 18, 2010

8:00am Start Time for Sunday, Dec. 19th, 2010

Think Snow!

STEVENS PASS MOUNTAIN WEATHER

12/18/2010 Weather

24HR SNAP SHOT starting at NOON today

Water .25  Snow - 2-4
Freezing levels - 2000'  Steady
Winds - 5-15 E


General Discussion: A low pressure system hanging off the Washington coast will spin bands of snow showers through the state today and tomorrow.

Long-term: This pattern of periodic bands of moisture passing through the Cascade Mountains will continue into next week. A slow warming trend will begin as warm air from the south infiltrates during the next few days. Freezing levels could be near Pass level by the middle of the week.


TRENDS AND TIMING
Precipitation: A few inches of snow will be possible as moderate snow showers pass through from time to time.

Freezing levels: Freezing levels will continue to hover near the 2000’ level today.

Winds: These brisk east winds will remain gusty through tomorrow.

December 17, 2010

8:00am Start Time for Satruday, December 18th, 2010

Todays Weather Feature - East flow

East west temperature gradients.  With Freezing levels as high as 4500' over Seattle and freezing levels below 1000' in Wenatchee, strong east west gradients are created in the mountain passess.

4k 850mb forecast model for tonight.
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STEVENS PASS MOUNTAIN WEATHER

12/17/2010 Weather

24HR SNAP SHOT starting at NOON today

Water < .10
Freezing levels - 1500' steady
Winds -  10-20 E  


General Discussion: The main weather feature today will be the cold east winds blowing through the Pass. Weak disturbances moving up the coast will bring snow showers to the mountains tomorrow.

Long-term: This pattern of passing snow showers will continue through the weekend and into early next week. No significant systems expected in the long term outlook.

TRENDS AND TIMING
Precipitation: Today will remain dry with snow flurries possible. Snow showers will begin around mid day tomorrow. Other than a few inches here and there from these showers, there is no significant accumulation is expected through the weekend.

Freezing levels: Cold air east of the crest will continue to hold freezing temperature low through the weekend.

Winds: East flow will strengthen today and remain strong through tomorrow. Ridge top winds could exceed 40mph tonight.

December 16, 2010

Start Time Friday---8:00am

STEVENS PASS MOUNTAIN WEATHER

12/16/2010 Weather

24HR SNAP SHOT starting at NOON today

Water - Lt >10  Snow - trace
Freezing levels - 1500' steady
Winds - 0-15  E


General Discussion:  Weak east west gradients continue today.  Thus, today and tomorrow will be cool, dry and partly sunny skies.

Long-term: A disturbance will move up from the south on Saturday bringing a chance of some more snow showers.   Nothing siginficant on the horizon. 

TRENDS AND TIMING
Precipitation: No significant precipitation expected for the next 24-48 hours.

Freezing levels: Freezing levels will hover between 1000’ and 2000’ for the next few days. Cool air filtering into the eastern basin will produce cold surface temperatures as well.

Winds: East flow will strengthen tonight.

December 15, 2010

Start Time Thursday---8:00am

East West Pressure Gradients

East West pressure gradients across the Cascades has been created from the High pressure centered over Idaho and Western Montana and the Low spinning in the Gulf of Alaska.  This is the culpret of pushing the moisture off the Washington coast tomorrow and Friday.

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STEVENS PASS MOUNTAIN WEATHER

12/15/2010 Weather


24HR SNAP SHOT starting at NOON today

Water - .25  Snow 2-4
Freezing levels - 2000' steady
Winds -  0-10 E


General Discussion: Bands of moisture will continue to produce snow showers through the central Cascades today.

Long-term: East/off shore flow will push moisture west of the mountains tomorrow afternoon. This will result in a dry Thursday night and Friday. A system tracking up the Californian/Oregon coast, will bring a chance of some more snow over the weekend.

TRENDS AND TIMING
Precipitation: Passing snow showers will continue over the Cascades today and part of tomorrow. Dry conditions will follow Thursday night and Friday.

Freezing levels: Freezing levels will stick around 2000’ for the next few days. Cold air from the interior NE will keep surface temps near or below 20f degrees.

Winds: East flow will develop tonight and strengthen tomorrow.

December 14, 2010

Start Time Wednesday---8:00am

Power Ski Cuttin in the mornin!

STEVENS PASS MOUNTAIN WEATHER

12/14/2010 Weather

24HR SNAP SHOT starting at NOON today

Water - .25-.5  Snow - 4-6
Freezing levels -  3000 dropping to 2000
Winds - 5- 15 W



General Discussion: A cold front finally passed through the PNW this morning. This will bring cooler temperatures and snow showers today.

Long-term: This intermittent snow showers pattern will continue through the weekend. We should receive a few inches of snow every day.


TRENDS AND TIMING
Precipitation: Moderate snow showers will continue through noon tomorrow. Convergence conditions developing this afternoon could enhance orographics and possibly bump up snow totals.

Freezing levels: Freezing levels will continue to drop as cooler NW air moves in. Freezing levels will hover near 2500’ for the next 24-36 hours.

Winds: Westerly flow will strengthen today as the convergence zone takes shape. I am not expected huge winds, but it will be possible to see gust in the 20-30mph range this evening. Winds will taper off early tomorrow morning and begin to shift easterly.

December 13, 2010

Start Time Tuesday---8:00am

STEVENS PASS MOUNTAIN WEATHER

12/13/2010 Weather

24HR SNAP SHOT starting at NOON today

Water - .5-.75  Snow - 4-8
Freezing levels - 5000' dropping to 3500'
Winds - 0-5 E shifting W tomorrow


General Discussion: A cold front driving in from the NW will bring another round of precipitation today and tomorrow.

Long-term: The precipitation will begin to taper off Wednesday afternoon as the atmosphere begins to stabilize. Thursday and Friday look dry for now.


TRENDS AND TIMING
Precipitation: Rain will slowly change to snow during the next 24hrs. Moderate snow will fall tomorrow with convergence conditions possible during the afternoon.

Freezing levels: Freezing levels will drop below pass level sometime around 4am tomorrow morning. Freezing levels will continue to drop during the day.

Winds: Light east flow will develop today. Westerly flow will override east flow after the cold front moves through early tomorrow morning. jdm

December 12, 2010

8:00 am Start Time for Monday, Dec. 13th,2010

Over 3.5 inches of precip. since this storm cycle began yesterday at 11:00am

STEVENS PASS MOUNTAIN WEATHER

12/12/2010 Weather

24HR SHAP SHOT starting at NOON today

Water - .75 Snow - 0
Freezing levels - 6500'  dropping 4500'
Winds - 5-10 WSW


General Discussion:  As expected, this big storm will play itself out today, with continued heavy precipitation, warm temps and breezy conditions.

Long-term: Tonight and tomorrow morning will be an interim period before the next system starts tomorrow afternoon. Moderate to heavy snow is expected on Tuesday.

TRENDS AND TIMING
Precipitation: Rain will begin to taper off this evening. Tonight and tomorrow morning will be relatively quiet. Mixed rain and snow showers will develop tomorrow afternoon.

Freezing levels: Freezing levels will begin to fall tonight reaching 4500’ by midnight. Freezing levels will slowly continue to fall, reaching 4000’ by Tuesday morning.

Winds: Breezy conditions will continue on the ridges today. Westerly flow will weaken this afternoon and begin to shift easterly tomorrow.

December 11, 2010

8:00 am start time for Sunday, Dec. 12th, except for a small crew for two AC routes.

Water amount model for 36hrs

Impressive water amounts.  Red = 5-8" of water.


STEVENS PASS MOUNTAIN WEATHER

12/11/2010 Weather

24HR SNAP SHOT starting at NOON today

Water - 2.5"  snow +12"
Freezing levels -  3500 rising to 7000'
Winds - 5-10 E shifting SW


General Discussion: As anticipated, a strong warm front with a significant amount of moisture will lift north through the state today. This will bring snow changing to rain for the next 24 -36 hours.

Long-term: The faucet is expected to turn off late tomorrow evening. The silver lining is that a nice looking winter storm, with cool NW flow, will slide in on Tuesday bringing back the snow.

TRENDS AND TIMING
Precipitation: Snow will arrive around noon today. Snow should continue into the evening before it changes to rain sometime around midnight. Storm totals look like this: .75-1” by midnight tonight – possibly +12” of snow depending when the east flow gives in. After midnight tonight an additional 2.5 -3”of rain for the following 24hrs will be possible.

Freezing levels: Freezing levels will hold near pass level today before they rise to 7000’ after midnight. East flow will help hold surface temperatures below freezing through most of today.

Winds: East flow is expected to hang in there until 10pm tonight. Strong SW flow will blow tomorrow through most of the day. Ridge top winds of 50mph or more will be possible. jdm

December 10, 2010

INCOMING

8:00 am Start Time for Sat. Dec. 11th, 2010

STEVENS PASS MOUNTAIN WEATHER

12/10/2010 Weather


24HR SNAP SHOT starting at NOON on today


Precipitation “ Water: .10
“ of Snow: 0-1
Freezing Levels - 3000’  falling to 2000’
Winds -  0-10 W shifting E 
General Discussion: Should be an epic pow day with 13” of new and even some sun breaks to boot. Snow will taper off today as high pressure briefly builds over the PNW.

Long-term: Dry condition will last through noon tomorrow with snow developing in the afternoon. An ugly storm with warm temperatures, heavy rain and high winds will arrive on Sunday. Cooler air with more precipitation will return during the first part of the week.

TRENDS AND TIMING
Precipitation: Snow showers will linger over the crest today and then taper off after 4pm. Heavy snow is expected between noon and midnight tomorrow. Snow is then expected to change to rain during the early morning hours. Sunday will be very wet, warm and windy. Storm totals by Monday are calculating out to be 2-4+” of water.

Freezing levels: Freezing levels will slowly fall from 3000’ to 2000’ as cool air fills in east of the crest today. Freezing levels will hold around 2500’ with east flow preserving below freezing surface temperatures through most of the day. Freezing levels will rapidly rise early Sunday morning reaching 6-7000’ during the day.

Winds: Westerly flow will weaken today and shift east overnight. East flow will strengthen tomorrow. SW flow will eventually override the east flow as the warm front moves in early Sunday morning. This storm has significant energy associated with it so expect periods of high winds. jdm

December 9, 2010

Start Time Friday-10th--6:15am

How do?
So far with this storm cycle there has not been much to look at. We gotten a lot of snow over the past several days but with warm temps, no wind and low snow cover avalanche activity has been minimal.

Early this afternoon things changed. With light wind developing and very intense showers we are seeing 12" crowns in places--self regulating.

Still not much snow out yonder but with  possible converg of Meriwethers forecast things may be different in the morning.

Those of you throwin powder take no prisoners. Buried sun crust on the south slopes that could produce later on, be good to break it up--ya know what I mean!!

Jon

STEVENS PASS MOUNTAIN WEATHER

12/9/2010 Weather


24HR SNAP SHOT starting at NOON today

Water - .5 .75  Snow 8-10+
Freezing levels - 4000' lowering to 3000'
Winds - 10-25 W  gusty

General Discussion: This active weather pattern will continue to produce moderate to heavy snow showers through tomorrow. Upper level ridging will bring a break in the action tomorrow and part of Saturday.

Long-term: A warm front driving up from the SW will bring rising freezing levels and potentially heavy precipitation to the mountains Saturday night and Sunday.

TRENDS AND TIMING
Precipitation: Moderate to heavy snow showers will continue through noon tomorrow. A heavy period of snow may occur tonight powered by a Puget Sound Convergence Zone. Snow will taper to light showers after noon tomorrow.

Freezing levels: Freezing levels will drop to 3000’ after midnight. Freezing levels will remain near the 3000’ level until Saturday.

Winds: Westerly flow will strengthen today. A strong wind event will be possible after closing today. Sustained winds of +25mph, with higher gust likely, will be possible through the night. Winds will taper off tomorrow morning. jdm

CONVERGENCE WINDS POSSIBLE TONIGHT -  Good orographics possible.
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December 8, 2010

Long range "watchout" for the weekend.

Warm air packed with some heavy precipitation developing for the weekend.  Keep and eye on this. 

Long Range MM5 precip for Saturday night.   Notice SW fetch of moisture.  Europe and Canadian models disagree with the detials on freezing levels.  Has the potential to be significant rain on snow event. 

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Complex weather

Lots of complexity going on in the vertical.  SW warm air advection scouring out cool air trapped east of the crest.  Couple this with a tripple point frontal system.  A big mystery bag for the next 24 - 48 hours.    

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Start Time Thursday 9th---8:00am

STEVENS PASS MOUNTAIN WEATHER

12/8/2010 Weather


24HR SNAP SHOT starting at NOON today

Water - .25 -.5  Snow 4-7
Freezing levels - 5000' falling
Winds - 5-10  SW  


General Discussion: A complex system will move through the PNW today bringing a mixed bag of precipitation to the mountains through tomorrow.

Long-term: There will be a lull in the activity on Friday and part of Saturday. The next in a series of systems will begin late Saturday or Sunday.


TRENDS AND TIMING
Precipitation: Today there will be mixed rain and snow changing to snow after midnight. A short rain period will be possible this afternoon. Snow will return after midnight when the temperatures begin to fall.

Freezing levels: Freezing levels will inch their way up to 5000’ later today and then begin to fall back down below pass level after midnight. With any luck the snow levels will stay around 4000/4500’.

Winds: East flow will end today with SW flow developing today. A westerly flow regime will be in place through the weekend. It will be possible to get some windy periods as these fronts move through. 

December 7, 2010

Start Time Dec. 8th---8:00am

Slowly - typo

Slowing inching its way east

STEVENS PASS MOUNTAIN WEATHER

12/7/2010 Weather


24HR SNAP SHOT starting at NOON today

Water - .5 snow 5-8
Freezing levels -  4000' -4500'
Winds -  5-10 E / SE

General Discussion: Radar shows the slow moving frontal system just entering the PNW this morning.

Long-term: The low pressure system churning in the Gulf of Alaska will continue to spin frontal bands into the PNW for the remainder of the week.

TRENDS AND TIMING
Precipitation: The first wave of moisture is currently moving into the mountains. Expect light snow this morning increasing this evening. Snow, with some rain mixed in will fall through the night.

Freezing levels: Freezing levels will hover between 4 - 4500’ today. It will be possible to get a small bump up in temperatures tomorrow when the SW flow kicks in.

Winds: East flow is expected to hold until SW flow finally erodes the cool air in the upper valley sometime tomorrow. I am not expecting any significant wind with these systems. jdm

December 6, 2010

Start Time Tuesday 7th---8:00am

Rest for it looks like we may get punished over the next week!!!

Big system out there.

STEVEN PASS MOUNTAIN WEATHER

12/6/2010 Weather


24HR SNAP SHOT starting at NOON today

Water - .25  Snow 2.4
Freezing levels - 3000 rising 4000
Winds 5-10 E   SW aloft


Will East flow save the day?  Time will tell.
General Discussion: Today will stay relatively dry with thickening clouds and high humidity. The pattern change will begin early tomorrow morning with the first push of moisture.

Long-term: The mountains will enjoy an active weather pattern for the remainder of the week. With some luck with the temperature, we should have good dose of snow.

TRENDS AND TIMING
Precipitation: Snow is expected after 4am tomorrow and should slowly ramp up during the following 24 hrs. Snow will be wet and heavy with periods of rain at pass level possible. The 72hr storm totals are calculating out to be 1.5-2” of water. However the precipitation models have been forecasting higher than actual amounts, so I am bit skeptical.

Freezing levels: The freezing level will continue to inch its way to 4000’ west of the crest today. Colder air trapped east of the summit will hold surface temperatures near or just below freezing.

Winds: Light east flow at the surface with SW flow aloft will remain in place through tomorrow. jdm

December 5, 2010

8:00 am Start time for Mon Dec. 6th, 2010.

Snow is coming!!!

The Jet

Notice the Jet dipping south - It is expected to flatten later this week and position itself over the PNW with a more favorable W to E orientation.    Could be a sporty storm cycle. 

Animation of Jet Stream Forecasts           Animation of Jet Stream Forecasts

STEVENS PASS MOUNTAIN WEATHER

12/5/2010 Weather

24HR SNAP SHOT starting at NOON today

Water - .10  Snow - 0-1
Freezing levels - 2500 rising 4000'
Winds - 5-10 E SE



General Discussion: The next few days will be relatively dry with the exception of a few small waves of moisture passing through. Warmer air will also make its way in tonight.

Long-term: Change is in the air. A large low pressure system is creeping its way toward the western coast. This will begin to drive a series of systems into the PNW starting late Monday night or early Tuesday morning. Expect an active weather pattern with plenty of moisture and warmer air to persist into next weekend.

TRENDS AND TIMING
Precipitation: A small wave of moisture will quickly move through after 4pm today bringing a brief light snow period.

Freezing levels: East flow and cool air aloft northeast of the crest, will keep surface temperature low as freezing levels rise to the west. Expect the freezing level to reach 4000’ by 4am tomorrow with east flow keeping surface temperatures below freezing.

Winds: East flow will weaken today but remain at the surface. jdm

December 4, 2010

8:00 am Start Time for Sunday Dec. 5th, 2010

Keep thinking snow...

STEVENS PASS MOUNTAIN WEATHER

12/4/2010 Weather

24HR SNAP SHOT starting at NOON today

Water - 0 Snow 0
Freezing levels - 1000' rising to 3000'
Winds - 5-15 E



General Discussion: The weekend will continue with dry and cool weather.

Long-term: A pattern change, fueled by a massive low pressure system building in the Gulf of Alaska, will bring warmer temperatures and moderate to heavy precipitation to the PNW. This will all begin to affect us late Tuesday night or Wednesday morning. This has potential to be an ugly storm with freezing rain, snow, heavy rain and flooding in the low lands. Confidence on the details is low, so I will wait until tomorrow or even Monday to see what this all means for the Pass.

TRENDS AND TIMING
Precipitation: Scattered clouds and sun breaks with no precipitation will continue today. A passing snow shower or two will be possible tomorrow.

Freezing levels: Freezing levels will begin to rise tomorrow morning. They are expected to rise to 2500’-3000’ by noon.

Winds: Brisk east flow will strengthen today. jdm

Vorticity (potential energy)

Massive low pressure cell -  500mb Vort.  Isobar tightly packed along southern boundary.   The concern is how far south it dips -  It has Pinaple Express qualities.   Snow or rain will depend on upper air temperature mixing with SW advection.

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December 3, 2010

8:00am Start Time for Satruday December 4th, 2010 

THINK SNOW!!!

STEVENS PASS MOUNTAIN WEATHER

12/3/2010 Weather

24HR SNAP SHOT starting at NOON today

Water - 0  snow 0
Freezing levels - 1000'  rising to 2500'
Wind - 5-10 E


General Discussion: Cool and dry condition will continue through the weekend.

Long-term: A fairly significant pattern change will begin on Monday as a large low pressure system moves toward the PNW coast. Details on what this means for the mountains are still fuzzy, but moisture and warmer temperatures will be a part of the equation for the start of the week.   See model below.

TRENDS AND TIMING
Precipitation: Other than a few light flurries, dry conditions will continue through the weekend.

Freezing levels: Freezing levels will drop below 1000’ tonight and then begin to rise tomorrow. Freezing levels will hover between 2k and 3k through Sunday.

Winds: East flow will develop today and strengthen tomorrow. jdm

Both of the low pressure systems over Northern latitudes are pretty impressive

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December 2, 2010

The Future

Interesting changes developing in the long term models.  The Low in the Gulf of Alaska is almost stationary.  The southern boundary of the low is very far south. This is allowing a enlongated mosture stream to be entrained. This can be the first signs of a storm track developing.  It will be intesting to watch what happens as the pattern changes early next week.


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MOUNTAIN WEATHER

12/2/2010 Weather


24hr SNAP SHOT starting at NOON today

Water - .10  Snow - Trace
Freezing Level - 2000' steady
Wind - 0-5 W


General Discussion:  A low pressure system, well off shore, will produce broken clouds and periods of light precipitation for the remainder of the week.

Long-term:   The weekend will continue to be dry with a few scattered snow showers possible. There is a pattern change beginning to develop during the first part of next week. Let’s hope this will bring a more favorable storm cycle for us.


TRENDS AND TIMING
Precipitation: Mostly dry conditions will prevail through the rest of the week. There is a chance of a passing snow shower or two. No significant accumulation expected until possibly next week.

Freezing levels: Freezing levels will hover near the 2000’ for the next 24 hours. Cool air from the NE will fill in tomorrow dropping freezing levels even more.

Winds: Light westerly flow will continue today. East flow will develop tomorrow.

Start Time Friday 3rd----8:00am

December 1, 2010

Start Time Thursday 2nd Dec.----8:00am

STEVENS PASS MOUNTAIN WEATHER

12/1/2010 Weather

24HR SNAP SHOT starting at NOON today

Water - .10  Snow - 0-1
Freezing levels - dropping to 1500'
Winds  - light WNW



General Discussion:  Well, the models over did the precipitation amounts.  Still managed to get +-.75 out of it -  should still be good skiing.    A few left over snow showers in between some sun breaks are in store for opening day.

Long-term: Light snow showers will continue as a weak system brushes the coast for the remainder of the week. The next system to watch will arrive on Sunday or Monday.

TRENDS AND TIMING
Precipitation: Just a few lingering snow showers today with no significant accumulation expected.

Freezing levels: Freezing levels will slowly drop today as cool air filters in from the north.

Winds: Light northerly flow aloft, with westerly flow at the surface, will keep the winds very low today. East flow is expected to develop on Friday. jdm

The next system developing
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0800 Thurs March 28th, No ABS