6:00 Thurs March 1st ABS

MOUNTAIN WEATHER FORECAST - UPDATE

Time and Day:  1000 Wednesday

No changes to this morning’s forecast.   The winds have just flipped to easterly with light snow showers beginning.  The radar has the leading edge of the front entering the South Sound area and should be leaning up against the western slopes soon.

Precipitation:

Today 24hr

water: .25-.5   snow: 3-5

Tomorrow’s 24hr

water: .25-.5  snow: 4-6

MOUNTAIN WEATHER FORECAST

Time and Day:  0700 Wednesday

The Snapshot:   Today will start out dry with intermittent snow showers expected tonight – similar to yesterday. Snow showers with sun breaks will finish out the week with the weekend trending dry and partly sunny.  

The Science

Current Observations:  It is partly cloudy this morning with the 24hr stake reading 5” of new snow.   21 base / 26 ridges is the temperature profile. The barometer has dropped to 1010mb’s and the winds are light and westerly.  The wind blew fairly consistently through the night. (5-10mph – gusting in the 20’s)   This morning’s radar has dry and partly cloudy conditions over the mountains and the next frontal band of precipitation still a ways offshore.  

The Forecast:  With the main batch of moisture still offshore we should start to see light snow starting to fall around noon today.  The parent low-pressure trough will slide SSW today which will shift the flow at Stevens Pass to ESE.  Light to moderate bands precipitation will spin through the mountains for the next 24-36 hrs.   

The Long Range:   The weekend will be mostly dry with clear periods. 

24hr values daily 4am to 4am.

Precipitation: Today 24hr water: .25-.5   snow: 3-5 Tomorrow’s 24hr water: .25-.5  snow: 4-6 Trend and Timing: Moderate passing snow showers will be the precipitation game for the next few days.

Temperature: Low: 24    High: 30 Freezing level: +- 3500’ Trend and Timing:    The freezing levels will rise to+- 3500’ today and remain near that level through tomorrow.

Winds Base: 0-5 E Ridge Top: 0-10 SE Trend and Timing: Winds will shift easterly at the surface with SSE winds aloft today.

8:00 Wed Feb 28th ABS

MOUNTAIN WEATHER FORECAST - Update

Time and Day:  1000 Tuesday  

No significant changes to this mornings forecast.   The timing and intensity for tomorrow' storm is still question.  

The Snapshot: Light snow, breezy with slightly warmer temperatures will be the weather pattern today and tomorrow.   A drying trend begins on Thursday with the weekend following suit.

The Science

Current Observations:  The satellite image has light snow falling in the mountains and a band of rain moving into the coastal region.  The temperature profile is 25 base / 19 ridges.   The barometer is 1013mb’s and falling and the winds are westerly and gusting 5-15mph.   

The Forecast:   A low pressure system will slowly slide down the Canadian Coast today.  This will push moisture into the region with light snow for Stevens Pass for most of the day.  

There is a weak triple point frontal associated with this low pressure system.  The models disagree on the impact of this system to Stevens Pass. The GFS model has the front stalling and weakening while the European model has it being a bit more potent.  As with previous triple point storms, we can expect the freezing levels to rise and fall with the passing of the fronts.  The flow also shifts easterly tomorrow which will help hold temperatures in check, but cancel out the westerly orographics (no convergence).   

The Long Range:  A prolonged dry period will begin on Thursday as a high pressure cell slowly drifts into the region. 

24hr values daily 4am to 4am.

Precipitation: Today 24hr water: .25-.5  snow: 4-6 Tomorrow’s 24hr water: .25-.5  snow: 4-6 Trend and Timing: Light snow will begin today and continue through the night.  There will be a lull in the snow tomorrow morning with light snow beginning again tomorrow afternoon.

Temperature: Low: 18    High: 28 Freezing level: 3500’ – 2500’- 3500’.   Trend and Timing:    The freezing levels will peak near 3500’ today and then fall tonight and then rise back up to +-3500’ tomorrow.

Winds Base: 5-10 W Ridge Top: 10-15 W Trend and Timing: Westerly flow will strengthen today with east flow developing tomorrow.

8am ABS Tuesday the 27th

Good work with the storm cycle over the weekend everyone. Enjoy the short break, active weather continues tomorrow and Wednesday. 

MOUNTAIN WEATHER FORECAST

Time and Day: 1030 Monday

The Snapshot:  Today will be mostly dry with sun breaks.  Light snow arrives tomorrow with a stronger storm brewing for Wednesday. 

The Science

Current Observations:  22” was the official 24hr snow total.  The temperature profile is 22 base / 17 ridges.  The barometer has climbed to 1013mb’s.   The winds are westerly and very light.  The radar has a few isolated snow showers lingering in the convergence zone, but for the most part, the atmosphere is stabilizing with partial clearing underway.  

The Forecast:   There will be a well-deserved break in the weather today as a weak upper-level ridge slides through.   NW flow kicks in tomorrow which will provide a day of light but consistent snowfall.  A low-pressure system, building in the Gulf of Alaska, will bring a stronger system with warmer temperatures and moderate to heavy precipitation (snow) to the mountains on Wednesday.      

The Long Range:   A drying trend begins on Thursday with broken clouds and mostly dry conditions persisting through the weekend.        

24hr values daily 4am to 4am.

Precipitation: Today 24hr water: .10  snow: 0-1 Tomorrow’s 24hr water: .25-.5  snow: 4-6 Trend and Timing: Mostly dry today with snow picking up after 4am tomorrow.

Temperature: Low:  16   High: 26 Freezing level: +-2500’ Trend and Timing:    Freezing levels will hover near 2500’ through the day with good overnight time cooling.

Winds Base: 0-5 W Ridge Top: 5-15 W Trend and Timing: Winds will be light today with the 5000’ winds picking up a bit tomorrow.

MOUNTAIN WEATHER FORECAST

Time and Day:  0500 Monday – The detailed weather forecast will be delayed until mid-morning.  

Today will be a recovery day with the snow games resuming tomorrow.  

The Snapshot:  Diminishing snow showers today with the next storm arriving early tomorrow morning and then another stronger storm on Wednesday -  “Out like a Lion”. 

The Science

Current Observations:  The 24hr precipitation total is +-18” snow / 1.7” of water.   The average winds are diminishing but still gusting in the 15-25mph range.   The temperature profile is 22 base / 16 ridges, and the barometer is at 1010mb and rising.    

6am Monday the 26th ABS

If you left me a note, you're on the list.

Backside never opened today, C3 was at 3pm. Wind hold on all chairs most of the morning. The skiing is good.

6am 6am 6am!! ABS Sunday the 25th

6am, tell your friends.

Mountain Weather Forecast

Time and Day: 0500 Saturday

The Snapshot: Snow showers with a midday break today, heavy snow beginning overnight and continuing tomorrow.

The Science

Current Observations:  4-5” overnight, with snow continuing at the moment. Temperatures have moderated a bit and are in the low 20’s across the mountain. Winds are light to moderate from the west. The barometer has dropped from 1022 millibars to 1006 at 4am as the low pressure center approaches.

The Forecast: Snow will continue this morning as the latest low pressure cell moves over Western Washington. Showers will taper off Saturday morning in a brief break between systems. The next, much stronger system, arrives Saturday night. This is a larger scale low pressure trough with steady, strong, westerly flow behind it. This is typically a good setup for frontal showers followed by a convergence zone aimed at Stevens Pass. Models currently have the convergence zone sitting over the forecast area for much of Sunday bringing heavy snow accumulations.

The Long Range: Monday looks like a mostly dry, cool day. The next system arrives early Tuesday morning for another round of snow. Freezing levels remain between 1,000 and 2,000 feet for next week.

24hr values daily 4am to 4am.

Precipitation: Saturday’s   24hr water:  .75   snow: 8-10” Sunday’s   24hr water:  1.25-1.5   snow: 12-18” Trend and Timing: Moderate snow ending Saturday morning, beginning again Saturday night and becoming heavy by 4am Sunday. Snow continuing in possible heavy convergence showers Sunday.

Temperature: Low: 18    High: 26 Snow level: 1000’ Trend and Timing:     Steady temps with daytime warming.

Winds Base: W 5-15 Ridge Top: W10-20, then WSW 30-40 with gusts Trend and Timing: Consistent west winds during the day Saturday, becoming gusty and moderate to strong Saturday night and Sunday am.

Calloff Saturday the 24th

6:00 ABS Saturday the 24th

That's right, 6:00am! We're gonna make the most of that daylight. 

Mountain Weather Forecast

Time and Day: 0720 Friday

The Snapshot: Get ready for a busy weekend! Continued cold temperatures with snow beginning this afternoon. A break in the action Saturday mid-day with more snow Saturday night.

The Science

Current Observations:  No measureable snow overnight, temperatures remain cold with the base area at 7 degrees and the upper mountain at 10. Winds are light from the W/SW. The barometer is basically steady.

The Forecast: A low pressure system in NW flow will drop into our area this afternoon and bring light to moderate snow with increasing winds. Winds will be westerly and moderate to strong which is favorable for a convergence zone to setup. The general pattern remains the same with high pressure in the Pacific, allowing cold north/northwest upper level flow to impact the PNW. There is a break between systems during the day Saturday with another, stronger, system moving into our region overnight Saturday. This second system has a more pronounced front and more moisture behind it, along with westerly winds and possible convergence. This will bring a snowy and stormy day on Sunday.

Snow nerd stuff: Actual snowfall totals are difficult to predict at cold temperatures. This is because of the properties of water vapor and how temperature affects it. A parcel of warm air can hold more water vapor than the same parcel of relatively colder air. At warmer temperatures, the snow is made up of a greater percentage of water (“denser”), and at lower temperatures there will be a higher quantity of snow produced from the same amount of water. It is because of this that from an avalanche forecasting perspective, we are often more concerned with the amount of water that fell from the sky than the amount of snow.

The Long Range: When it’s on, it’s on. There’s a reason we have glaciers. After a relative break on Monday, another system affects the region Monday night and Tuesday. Storms continue at winter temperatures during next week. Details will emerge as time allows.

24hr values daily 4am to 4am.

Precipitation: Friday’s   24hr water:  .75   snow: 8-12” Saturday’s   24hr water:  .75   snow: 8-12” Trend and Timing: Snow starting after 12pm Friday, becoming moderate overnight ending Saturday morning. Beginning again Saturday night.

Temperature: Low: 7    High: 22 Snow level: 0-500’ Trend and Timing:     Daytime warming, with a warmer airmass between 4pm and 7pm, then cooling down.

Winds Base: W10-15 Ridge Top: WSW 25-30 with gusts Trend and Timing: Winds will be calm Friday morning, becoming moderate to strong and gusty Friday night.

8:00 Fri Feb 23rd no ABS

MOUNTAIN WEATHER FORECAST

Time and Day: 0700 Thursday

The Snapshot:  Clear and mostly dry today with snow arriving tomorrow afternoon.  Snow showers are expected through the weekend.

The Science

Current Observations:  1” of snow fell overnight with clear conditions being reported this morning.  The temperature profile is 10⁰ base and 4⁰ ridges.  The winds are light and out of the east and the barometer has risen slightly to 1015 mb’s.  The satellite radar has, with the exception of some light snow falling in the Columbia Gorge, dry conditions for most of the state.

The Forecast:  An upper-level ridge will nudge into the mountains today producing a mostly dry day.  The flow shifts NW tomorrow with and embedded cold front in tow.  Snow arrives early tomorrow afternoon with convergence conditions possibly setting up.  Moderate post front winds can be expected tomorrow night but they should be fairly short-lived.

The Long Range:  The snow will diminish Saturday morning with a short dry period and sun breaks Saturday afternoon.  Another system arrives early Sunday morning with more snow. Temperatures will remain on the cold side through the weekend with more seasonally average temperatures expected next week.       

24hr values daily 4am to 4am.

Precipitation: Today 24hr water: lt.10  snow: trace Tomorrow’s 24hr water:.75   snow: 6-10" Trend and Timing:  Dry today with snow arriving afternoon tomorrow.

Temperature: Low:10     High: 20 Freezing level: Sea level -500’ Trend and Timing:    Cold temperatures will remain in place today with some gradual warming starting tomorrow.

Winds Base: 0-5 E Ridge Top: 5-10 E Trend and Timing: East flow will continue into early tomorrow morning and then shift westerly with the arrival of tomorrow’s front.  A post front wind event should be expected late tomorrow afternoon with gust 20-25mph.

8:00 Thur Feb 22nd no ABS

MOUNTAIN WEATHER FORECAST

Time and Day: 0700 Wednesday

The Snapshot:  I hope you are catching the sunrise this morning with the beautiful mountain alpenglow.   It will be cold again today with some clouds and light snow moving in tonight.  Slow warming and snow developing on Friday with snow continuing through the weekend.   

The Science

Current Observations:  The mercury has dipped to 3 degrees in the base area and 1 degree on the upper mountain this morning.  The winds are light and out of the east.  This morning’s satellite image has clear skies over the North Central Cascades and a midlevel stratus layer of clouds to Northwest. 

The Forecast:   Today will be much like yesterday with cold temperatures, sun breaks, and light snow showers.  The general flow will shift NW tonight with a weak disturbance sliding through.  Tomorrow will be another cold and mostly dry day.

The next storm of interest arrives Friday afternoon with moderate snow likely. It is a still a bit far out to get hung up on the details, but for now, the models show 6-10” of snow for Saturday morning. 

The Long Range: There are several disturbances developing along the British Columbia coastline which will continue to track through the PNW over the weekend.  Freezing levels will be on the rise but remain well below Pass level.  Therefore, expect snow for the entire weekend.     

24hr values daily 4am to 4am.

Precipitation: Today 24hr water: lt.10  snow: trace Tomorrow’s 24hr water:.10   snow: trace Trend and Timing: Mostly dry with a light snow shower or two tonight.

Temperature: Low: 0    High: 18 Freezing level: Sea level Trend and Timing:    Freezing levels will remain close to sea level today with daytime warming into the high teens.

Winds Base: 0-5 E/N Ridge Top: 5-10 E Trend and Timing: Winds will be light and shift between East and North over the next 24hrs.

8:00 Wed Feb 21st no ABS

MOUNTAIN WEATHER FORECAST

Time and Day: 0630 Tuesday

The Snapshot:  This cold and mostly dry weather pattern will persist through Thursday with warming and potential measurable snow for the weekend.

The Science

Current Observations:  It is clear this morning with a balmy temperature of 9 degrees.  The barometer is holding steady at 1014mb’s with the winds blowing lightly out of the west.  Satellite radar has snow falling out along the coast and the south I-5 corridor.  The rest of the state is dry with broken high cirrus clouds overhead.

The Forecast:  A weak off-shore low-pressure system tracking south is the source of the high clouds and the snow in southwest lowlands.  A weak snow shower or two may sneak in today but, for the most part, we will remain mostly dry and cold through Thursday.   

The Long Range:  A fairly strong frontal system is setting up to bring snow late Friday afternoon.  It is a bit far out for strong confidence in the details, so stay tuned.       

24hr values daily 4am to 4am.

Precipitation: Today 24hr water: lt.10  snow: trace Tomorrow’s 24hr water: 0  snow: 0 Trend and Timing: Mostly dry through early Friday morning.

Temperature: Low: 9    High: 20 Freezing level: 0-500’ Trend and Timing:    Freezing levels will remain low through the next 24-48hrs.

Winds Base: 0-5 W to E Ridge Top: 0-10 W to E Trend and Timing: Weak east flow is expected to develop today.