February 23, 2017

8:00 Start Friday February 24th, No ABS


MOUNTAIN WEATHER FORECAST

Time and Day: 0700 Thursday

The Snapshot:   Today expect a few clouds, some sun and a snow shower or two.  Same goes for tomorrow but with a better chance of snow tomorrow afternoon.  Saturday will be mostly dry with snow expected on Sunday.

The Science:   NW flow has brought a colder airmass with isolated snow showers riding along for fun.  Most of the moisture is happening along the southwestern slopes of the Cascades with the northern portion of the state dry.  A low-pressure trough will spin more bands of moisture into the mountains tomorrow as it makes its way south along the coastal waters.  Hopefully, Stevens will squeeze a few inches out of this before it departs into Oregon tomorrow evening. 

Another similar low-pressure system slides down the coast on Sunday with some more snow possible.  Saturday will be left in between systems with little to no moisture expected.    

The Long Range:   Long range models are in an argument on what will happen next week.  The GFS has high pressure sliding into place, confining the moisture to the north; while the ECMWF (Euro) is forecasting snow.   All will be revealed in time – go European.   

Precipitation Ending at 4am:
Today 24hr water = .10 snow =trace
Tomorrow’s 24hr water = .25+ snow = 2-4

Trend and Timing:
A light snow shower or two will be possible today with a better chance of a few inches tomorrow afternoon.


24hr temperature ending at 4 am tomorrow: 
Low: 20    High: 32
Freezing level: -2000’

Trend and Timing:   
Freezing levels will be well below Pass level, but daytime recovery will be good with the aid of the sun.

 
24hr Winds (mph) ending at 4 am tomorrow:
Base: 0-5 WNW
Ridge Top: 0-10 WNW

Trend and Timing:
The wind will be calm and out of the WNW through tomorrow.



jM

February 22, 2017

8:00 Thur Feb 23rd no ABS

MOUNTAIN WEATHER FORECAST

Time and Day: 0630 Wednesday

The Snapshot:  A mixed bag of broken clouds with a few passing snow showers will be the weather pattern for the remainder of the week.   

The Science:  Cool unstable NW flow will bring lower temperatures and passing snow showers today.  A series of weak low-pressure systems will slide down the NW coast over the next few days.  The bulk of the moisture will remain offshore with a few isolated showers making it to the mountains.  This pattern will likely continue into the weekend.   

The Long Range:  The next chance of measurable snow may be early next week as the northern jet stream strengthens and more moisture becomes available.     

Precipitation Ending at 4am:
Today 24hr water = > .25  snow = 1-3
Tomorrow’s 24hr water = <.25 snow = 1-3

Trend and Timing:
Light snow showers with dry periods for the next +48hrs.


24hr temperature ending at 4 am tomorrow: 
Low: 18    High: 26
Freezing level: 2500’ – 1500’

Trend and Timing:   
Freezing levels will fall to or just below 2000’ by early tomorrow morning.  Surface temperature will rebound during the day to the mid to upper 20’s. 

 
24hr Winds (mph) ending at 4 am tomorrow:
Base: 0-5 WNW
Ridge Top: 5-10 NW

Trend and Timing:
Light NW winds will be the flow pattern today.  East flow returns tomorrow afternoon.



jM

February 21, 2017

8:00 Wed Feb 22nd no ABS

MOUNTAIN WEATHER FORECAST

Time and Day: 0700 Tuesday

The Snapshot:  Light snow showers with cooler temperatures are expected for the remainder of the week.

The Science:  Well, the extra snow that we expected yesterday decided to stay to the south after all.  3” of snow fell overnight with light snow falling at this hour.  There is another weak system working it’s way across the southern portion of the state, but like yesterday, most of the energy is expected to stay south and east of Stevens Pass.  Light snow showers with some clear periods will be the main weather game for the remainder of the week.  

The Long Range:   The pattern shifts to cooler NW flow over the next few days which will drop freezing levels and provide some passing snow showers from time to time.  This is not a lot of available moisture hanging around in the North Pacific waters; so no significant snow will be likely in the long-range 3-7 day forecast.   


Precipitation Ending at 4am:
Today 24hr water = .10  Snow = 0-1
Tomorrow’s 24hr water = <.25 snow = 1-2

Trend and Timing:
Light snow showers expected for the remainder of the week.  


24hr temperature ending at 4 am tomorrow: 
Low: 22    High: 32
Freezing level: +- 3000’  falling

Trend and Timing:   
Freezing levels will slowly fall to around 2000’ or lower over the next 24-48hrs  

 
24hr Winds (mph) ending at 4 am tomorrow:
Base: 0-5 NW
Ridge Top: 5-10 WNW

Trend and Timing:
Winds will be light out of the WNW for the next few days.



jM