6:15 start Tue Mar 1st abs

MOUNTAIN WEATHER FORECAST

Time and Day: 0900 Monday 

The Snapshot:  A beautiful Lead Day morning with 10” of new snow.  Today will be partly cloudy with some light passing snow showers possible.  Mixed rain and snow begins tomorrow with and an active week of weather ahead.  

The Science:  A high-pressure ridge between storms will create some partial clearing today.  A strong triple-point frontal system arrives early tomorrow morning with moderate to heavy snow and rain.  This system is packing a punch with high water contents (+1”) and strong winds.  The precipitation will likely start out as snow with east flow influence, and then slowly turn to mixed rain.  A cold front will switch the precipitation back to snow early Wednesday morning with snow showers tapering off through the day.

The Long Range:  Hit repeat Wednesday night as a another strong snow/rain/snow event forms.  Storms will continue to move through the PNW every other day or so into early next week.

Precipitation Ending at 4am: Today 24hr water = .25 Snow = 2-4 Tomorrow’s 24hr water = +-1”  snow = 3-8 Trend and Timing: The main event arrives after midnight tonight with moderate to heavy snow and rain falling through the day.  Snow tapers off by noon or so tomorrow.

24hr temperature ending at 4 am tomorrow:                                        Low: 26    High: 34 Freezing level: +- 4000’ – 5500’. Trend and Timing:    Freezing levels will hover around 4000’ into early tomorrow morning.  Freezing levels are expected to spike to near 6000’ tomorrow afternoon and then fall back below pass level sometime during the night.

24hr Winds (mph) ending at 4 am tomorrow: Base:  0-5 E Ridge Top: 5-10 ESE Trend and Timing: Light east flow will form this afternoon with SE flow aloft.  Winds increase with the arrival of tomorrows front.

jM

6:15 Start Monday February 29

Yes ABS.

MOUNTAIN WEATHER FORECAST

Time and Day: 0630 Sunday

The Snapshot: Light rain starting soon, switching to moderate to heavy snow and gusty winds during the day and overnight. Calm and mostly dry on Monday.  

The Science: A warm front is currently crossing the North Cascades which will be swiftly followed by the trailing cold front. Cold frontal passage should be midday Sunday. As the low pressure trough crosses Washington State, strong upper level zonal (westerly) flow will support good orographic snow showers with cold air filling in and lowering freezing levels. Convergence is currently indicated by models to set up north of Stevens Pass, near Glacier Peak. However, if this shifts south we could see higher amounts of snow.  

Weak high pressure will build behind the trough ending precipitation Monday morning, this will be short lived as the next moderate warm (5,000' snow level) front will cross Stevens Pass Monday night. There should be cool east flow in place for this event which may keep precipitation as snow for Stevens.  

The Long Range: Active weather continues throughout the week, with fronts every 24-36 hours and fluctuating snow levels.  

Precipitation Ending at 4am: Today 24hr water = .75               Snow = 6-8" (possibly more in convergence) Tomorrow’s 24hr water =  <.25        Snow = 0-2" Trend and Timing: Light rain will start the day, switching to snow mid-morning. Moderate (to heavy if convergence sets up) snow will increase through the afternoon and overnight, ending Monday morning.

24hr temperature ending at 4 am tomorrow: Low: 26 High: 34 Freezing level: 4,000' - 2,000' Trend and Timing: The warmest temperatures of the day should be at daybreak, with cold air rushing in during the day and lowering snow levels overnight.

24hr Winds (mph) ending at 4 am tomorrow: Base: 0-5 E then 10-15 W Ridge Top: 5-10 E then 20-30 W Trend and Timing: Light east winds will shift around the compass rose and become strong and gusty from the west midday and overnight Sunday.   253 Dan

8:00 Start Sun Feb 28th no abs

MOUNTAIN WEATHER FORECAST

Time and Day: 0630 Friday

 

The Snapshot:  Very light rain last night (no snow accumulation), clearing and drying trend today through Sunday morning, moderate snow beginning Sunday and ending Monday morning. 

 

The Science:  Last night's very weak frontal passage is giving way to building high pressure this morning. Showers will end as the short-lived ridge moves over Washington state today and exits the region Sunday. A weak embedded warm front may brush North-Central Washington Saturday night without much impact. Right on it's heels will be a more organized cold front with strong post-frontal west winds which will affect Stevens Pass Sunday mid-day into Monday morning. This can be a good setup for convergence showers for Stevens but currently it looks like the sweet spot will be closer to Glacier Peak. High pressure briefly rebuilds for Monday with another strong warm front Monday night. 

 

The Long Range:   The weather remains active for next week with nothing particularly impressive but continued precipitation at varying snow levels every 24-36 hours. 

 

 

Precipitation Ending at 4am:

 

Today 24hr water = .10     Snow = 1-2"

 

Tomorrow’s 24hr water = .5     Snow = 4-6"

 

Trend and Timing:

Precipitation will end this morning and pick back up again Sunday mid-morning. Moderate snow showers will continue Sunday into Monday morning before ending.

 

 

24hr temperature ending at 4 am tomorrow: 

                                     

Low:  30   High: 36

Freezing level: 4000-4500’

 

Trend and Timing:   

Cooler temperatures this morning will give way to partly sunny and warmer conditions this afternoon. 

 

 

24hr Winds (mph) ending at 4 am tomorrow:

Base:  5-10 W, 5-10 E

Ridge Top: 10-20 W, 10-15 E

 

Trend and Timing:

Moderate west winds will end this morning, giving way to light and variable winds during the day Saturday, before shifting to easterly Sunday morning.                                 -253

8:00 Start Saturday Feb 27 NO ABS

MOUNTAIN WEATHER FORECAST

Time and Day: 0700 Friday

The Snapshot: Increasing clouds today with light to moderate rain this evening. Rain will switch to snow showers overnight and Saturday morning before clearing and warming on Saturday afternoon.  

The Science: An elongated north-south oriented cold front is just offshore this morning and is pushing the high pressure ridge that the West Coast has been under to the east. Clouds will increase ahead of the weak front during the day today. A transitory high pressure ridge will build behind the front on Saturday and move east across the forecast area Sunday.

The Long Range:   A stronger front with lowering freezing levels will cross Stevens Pass on Sunday night with the potential for moderate snow. High pressure rebuilds for Monday and Tuesday.  

 

Precipitation Ending at 4am: Today 24hr water = .25-.5 Snow = 1-3" Tomorrow’s 24hr water = <.25 snow = 0-2" Trend and Timing: Precipitation will start out as rain around sunset tonight. It will switch to snow after midnight and Stevens Pass will see an inch or two before it turns to light snow showers which will end Saturday mid-morning.

24hr temperature ending at 4 am tomorrow: Low: 30 High: 36 Freezing level: 7000’ - 4000' Trend and Timing: As the warm air is pushed east, the temperature and freezing level will drop this afternoon. Freezing level will be around 5,000' when the precipitation starts, and lower further to pass level by 4am Saturday.

24hr Winds (mph) ending at 4 am tomorrow: Base:  0-5 E then 5-10 W Ridge Top: 0-10 SSE then 10-20 WSW   Trend and Timing: East flow will continue until frontal passage this evening, then winds will shift to westerly and increase until Saturday morning.     253 Dan

8am Start Friday, Feb 26 NO ABS

Latest pit from near the top of Sidewinder (Cowboy Ridge) on a west aspect. Nothing concerning or all that surprising, just right side up, well bonded powder skiing. We like the PNW in spring :)

Look for changes coming this weekend, with some rain at first but then snow by Sunday.

-253

MOUNTAIN WEATHER FORECAST

Time and Day: 0700 Thursday

The Snapshot:   Mostly clear with some morning fog and a few high clouds today.  Clouds begin to increase tonight with rain expected tomorrow night.

The Science:  This morning’s IR satellite has mostly clear skies throughout the state.  Clouds will increase during the next 24hrs as the high-pressure ridge slowly drifts east.  This will open the door for a frontal system to move through the mountains tomorrow night.   Freezing levels will continue to be above 5000’ through early Saturday morning, so expect most of the precipitation to be in the form of rain.    

The Long Range:   A cold front moves in on Saturday dropping temps and changing the rain to snow just before it tapers off.   Another front moves in on Sunday with some fresh snow heading into the new week. 

Precipitation Ending at 4am: Today 24hr water = 0 Snow = 0 Tomorrow’s 24hr water = 0 snow = 0 Trend and Timing: 0

24hr temperature ending at 4 am tomorrow:                                        Low:  30   High: 45 Freezing level: +6500’ Trend and Timing:    Good early morning cooling with temperatures climbing back into the mid 40’s today.   Freezing levels will remain well above Pass level through late Friday night.

24hr Winds (mph) ending at 4 am tomorrow: Base:  0-5 ESE Ridge Top: 0-10 SSE Trend and Timing: East flow at the surface with southerly flow along the ridge tops will be the wind regime for the next 36+ hrs.

jM

8:00 Start Thursday Feb 25, NO ABS

MOUNTAIN WEATHER FORECAST

Time and Day: 0700 Wednesday

The Snapshot:  Partly cloudy, dry and warmer will be the weather pattern for the remainder of the week.  Rain is expected late Friday.    

The Science:  Hi cirrus clouds blanketing the state will thin and begin to drift east as the pressure rebounds today.  With the aid of the sun and warm SW flow, temperatures could hit 50^0f  today and then again tomorrow.  

The Long Range: Models have a frontal system arriving late Friday afternoon.  Freezing levels will be +-7000’ for the start of this storm with rain likely Friday night.  There could be a bit of snow on Saturday before the precipitation tapers off during the day.   

Precipitation Ending at 4am: Today 24hr water =  0 Snow = 0 Tomorrow’s 24hr water =  0 snow = 0 Trend and Timing: Dry through Friday morning.

24hr temperature ending at 4 am tomorrow:  Low: 26   High: 48 Freezing level: 4500’ -  6000’ Trend and Timing:    Freezing levels are expected to top 6000’ this afternoon.

24hr Winds (mph) ending at 4 am tomorrow: Base:  0-5 SE Ridge Top: 0-10 SE Trend and Timing: Light southeasterly winds at the surface with southerly flow aloft will be the general flow pattern through Friday.

jM

8:00 Start Wed Feb 24th no abs

MOUNTAIN WEATHER FORECAST

Time and Day: 0700 Tuesday

The Snapshot:  A bit of morning fog this morning with dry weather expected for the rest of the week.  

The Science:  High pressure has stabilized the atmosphere over the state.  High clouds will move in later today in response to a weak system bumping up against the coast. Little to no precipitation is expected to make it to the interior.  

The Long Range:  The high pressure begins to shift east on Friday. Southerly flow aloft will allow the temperature to climb slowly through the week with freezing levels reach +6000’ or so.  So, at this point in the game, rain is on the docket for Friday night/Saturday.   

Precipitation Ending at 4am: Today 24hr water = 0 Snow =0 Tomorrow’s 24hr water = 0  snow =0 Trend and Timing: Dry through Friday.

24hr temperature ending at 4 am tomorrow:                                        Low: 24  High: 32 Freezing level: +-4000’ – 5000.' Trend and Timing:    Freezing levels will be around 4000’ but with east flow influence holding temperatures low.   Freezing levels will ascend above 5000’ sometime tomorrow afternoon.  Expected melt/freeze temperature swing to continue through Thursday – for you weather/science geeks out there; that is a diurnal temperature pattern.

24hr Winds (mph) ending at 4 am tomorrow: Base: 5-10 E Ridge Top: 5-10 E Trend and Timing: Gusty pass level easterly winds will be possible today.

jM

7:59 am Start Tue Feb 23rd no abs

MOUNTAIN WEATHER FORECAST

Time and Day: 0730 Monday

The Snapshot: Diminishing snow showers today with a dry and clear weather pattern developing tonight.   

The Science:  Light snow showers lingering in the mountains this morning will begin to dry up as high pressure builds over there region.  The stabilizing atmosphere will clear the skies tonight with a melt/freeze pattern developing through the week.

The Long Range:  Clouds move in on Wednesday, but high pressure will continue to dominate the weather pattern possibly into the weekend.    

Precipitation Ending at 4am: Today 24hr water = .10 Snow = 1-2 Tomorrow’s 24hr water = 0 snow = 0 Trend and Timing: Snow showers will taper off by this afternoon.

24hr temperature ending at 4 am tomorrow:                                        Low: 20    High: 28 Freezing level: +-3000.' Trend and Timing:    Clearing will allow temperatures to fall in the lower 20’s or even upper teens early tomorrow morning.  A melt freeze cycle could form this week.

24hr Winds (mph) ending at 4 am tomorrow: Base:  0-5 W Ridge Top: 0-10 W Trend and Timing:  Light westerly flow today shifting east tomorrow.

jM

8:00 Start Mon Feb 22nd no abs

MOUNTAIN WEATHER FORECAST

Time and Day: 0730 Sunday

The Snapshot:  Snow is expected to develop this afternoon with dry and clear conditions developing during the new week.

The Science:  This morning’s satellite imagery has clouds moving into Puget Sound with a following band of moisture still off shore.  The precipitation is expected to reach the mountains later today with snow falling through the night.  East flow and cool air aloft will help keep freezing levels in check for the moisture to be mostly snow.   

The Long Range:  Next week will trend dry and warm as high pressure builds over the west coast.

Precipitation Ending at 4am: Today 24hr water = .25-.5 Snow = 3-6 Tomorrow’s 24hr water = < .25  snow = 1-3 Trend and Timing: The snow is expected to begin late this afternoon.  Models have this storm weakening as it tracks east, therefore, expect intermittent showers persisting through the night.  The precipitation ends around noon tomorrow.

24hr temperature ending at 4 am tomorrow:                                        Low: 24    High: 32 Freezing level: 2500’ – 4000.' Trend and Timing:    Freezing levels will briefly spike to 4000’ this afternoon and then fall through the night.

24hr Winds (mph) ending at 4 am tomorrow: Base:  0-5 E shifting W Ridge Top: 0-10 E shifting W strengthening Trend and Timing:  The flow will shift westerly with the passing of the front this afternoon with gusty westerly winds expected.

jM