THE WEATHER

12/20/2007 Weather Discussion: A strong Puget Sounds Convergence band positioned right over the Hwy 2 corridor is the cause of our morning snow intensity. Things should begin to calm down and dry out once the cool NW flow takes shape. Looking at a 24 – 36 hour break before Saturday’s storm hits. Long-term models show Saturday’s storm total currently calculating out to be +-1.3” of water with freezing level between 4 and 5K. That could and probable will change one way or another. Another storm is on the heels of Saturday’s system for Sunday/Monday. The NW jet looks like it will keep an active weather pattern over the PNW for most of next week. Forecast from Thursday 4pm to Friday 4am Precipitation .25 in. Water 1-3 in. Snow Temperatures Low 16 High 24 Winds 5-10 NW Forecast for Friday 4am to 4pm Precipitation Lt .10 in. Water trace in. Snow Temperatures Low 16 High 22 Winds 0-5 WSW TRENDS AND TIMING Precipitation: Snow should taper to lingering mountain snow showers by 4pm today. Will keep a chance of snow in the mountains tomorrow but should be just an occasional shower or two. No accumulation expected between 4am tomorrow and 2am Saturday. Freezing levels: Freezing levels are expected to drop to near 2500’ by 10pm tonight. They should stay put tomorrow and then begin to rise early Saturday morning. Winds: The westerly Convergences winds should subside today by noon. A northwest flow will move in. A westerly then southwesterly swing will happen tomorrow as Saturday’s system starts to effect us. PS I will be gone for a week, so I will not be writing forecasts. You can refer to the Northwest Avalanche Centers forecasts at: http://www.nwac.noaa.gov/~nwac/products/SABNW

THE WEATHER

12/19/2007 Weather Discussion: A warm front quickly followed by a cold front will produce a good amount of snow today. A dry cooler air mass will usher in behind the cold front and begin to dry things out tomorrow. Long-term models show Thursday evening and Friday relatively dry. The jet will dip south once again on Saturday setting us up for the next storm cycle. Saturday’s storm currently has some strength to it with gale force winds hitting the coast from the south. Forecast from Wednesday 4pm to Thursday 4am Precipitation .5 in. Water 4-6 in. Snow Temperatures Low 24 High 32 Winds 5-15 SW Forecast for Thursday 4am to 4pm Precipitation .25 in. Water 2-4 in. Snow Temperatures Low 20 High 26 Winds 5-10 NW TRENDS AND TIMING Precipitation: Still expecting in the neighborhood of .75 - 1” of water between 4am and 4pm today. Snow should slowly convert to a showery pattern overnight and tomorrow. Precipitation should be done after 4pm tomorrow. Freezing levels: The warm front should be through the mountains by noon today. A cold front should quickly follow and thus see the temps drop over night. Freezing levels expected to lower below 2000’ by midday tomorrow. Winds: Strong frontal winds expected between fronts today. Could see ridge top SW/W winds of 40+ around noon today. The erratic winds should settle into a nice NW flow by midday tomorrow.

THE WEATHER FOR TUESDAY

12/18/2007 Weather Discussion: The PNW snow machine will continue for the next few days as storms continue to track through the mountains. Expecting a jump in temps this afternoon. Windy and snowy tomorrow. Long-term models show a possible break in the unsettled weather by Thursday or Friday as a high-pressure ridge develops. Another storm track seems to be setting up to bring us more wintery weather for the weekend. Forecast from Tuesday 4pm through Wednesday 4am Precipitation .5-.75 in. Water 8-10 in. Snow Temperatures Low 25 High 34 Winds 10-15 W Forecast for Wednesday 4am to 4pm Precipitation .75-1 in. Water 8-14 in. Snow Temperatures Low 24 High 30 Winds 5-10 SW TRENDS AND TIMING Precipitation: Steady moderate snow should continue through the night. Could see some heavy wet snow with a little rain mixed in there at the pass level this afternoon. Should turn back to all snow after 7pm tonight. A period of moderate to heavy snow expected tomorrow morning after 4am as another front pushes through the mountains. Snow expected to taper off on Thursday. Freezing levels: There is a spike in freezing levels indicated that could raise freezing levels to near or above pass level after noon today. Freezing levels should begin to fall back below pass level by 7pm tonight and hover near the 3500’ mark until Thursday when it will drop some more. Winds: The east flow will give way to a westerly flow overnight. Models are showing a strong westerly push around 10pm tonight with gust around 40+mph. Could be a windy day tomorrow.

THE WEATHER

12/15/2007 Weather Discussion: Snow should slowly taper off to showers today with a drier period tonight and the first part of tomorrow. The next system arrives tomorrow night. Long-term model show a snowy week ahead as systems continue to line up for their shot at the PNW. Currently, the timing of these systems is for tomorrow night one Tuesday and then other one for Thursday/Friday. “Game on” Forecast from Saturday 4pm to Sunday 4am Precipitation .25 in. Water 2-4 in. Snow Temperatures Low 24 High 30 Winds 5-10 SW Forecast for Sunday 4am to 4pm Precipitation Lt .25 in. Water 1-3 in. Snow Temperatures Low 25 High 32 Winds 0-10 S TRENDS AND TIMING Precipitation: Convergence winds with good orographics could dump 5 or more inches today. The winds should shift this afternoon, which should be the beginning of the end of the main snow. Snow showers should stick on the crest through the night and tomorrow. Snow from the next system expected to arrive after 4pm tomorrow. Freezing levels: Freezing levels should hover between 2500 and 3000’ for the next 12 hours. The southerly influence will raise temps to 3500’ or above tomorrow. Temps should drop back down with the passing of tomorrow night’s cold front. Winds: Westerly winds slowing and shifting to a southerly flow overnight. Should remain S/SE until Sunday night’s front drives westerly once again.

THE WEATHER

12/14/2007 Weather Discussion: Our winter storms are still on track to bring us snow this weekend. A warm front quickly followed by a cold front will generate windy conditions and snow tonight and most of tomorrow. Long-term models show a second stronger system arriving Sunday followed by continued unsettled weather for most of next week. Freezing levels looking good for snow throughout these storms. Forecast from Friday to Saturday 4pm 4am Precipitation .5 in. Water 4-6 in. Snow Temperatures Low 22 High 32 Winds 5-15 E Forecast for Saturday 4am to 4pm Precipitation .5 in. Water 4-8 in. Snow Temperatures Low 22 High 25 Winds 10-20 W TRENDS AND TIMING Precipitation: Snow developing after 4pm today and intensifying over night. The heaviest snow period appears to be in the early morning hours (2am –6am) Snow should begin to lighten up after 4pm. There should be a lull in the activity Saturday night before the next system arrives Sunday morning. Storm totals by Sat 4pm +-1” of water. Freezing levels: The approaching warm front will rise freezing levels to near 4000’ this afternoon but should be short lived. East flow will allow surface temps to remain below freezing thus keeping any threat of rain out of the picture. Freezing levels expected to drop below 3000’ through tomorrow. Winds: East flow should strengthen as the fronts approach tonight. East flow will eventually be overtaken by a strong westerly after 4am tomorrow morning. Good potential for a Puget Sound Convergence to be initiated for most of tomorrow morning.

John Meriwether

12/13/2007 Weather Discussion: Some low level warm air advection associated with the shifting jet stream is the culprit of our freezing drizzle. Mountain snow developing today as frontal bands of moisture precede the larger front tomorrow night. Long-term models show Saturday’s storm setting up nicely. We should begin to feel the effects late Friday night or early Saturday morning. Another storm is tracking in for Sunday/Monday and then another has potential for Tuesday. All in all should be a busy week of weather. Forecast from Thursday 4pm to Friday 4am Precipitation .25 in. Water 2-4 in. Snow Temperatures Low 25 High 32 Winds 5-10 W gusty Forecast for Friday 4am to 4pm Precipitation .25 in. Water 1-3 in. Snow Temperatures Low 28 High 34 Winds 0-5 SW TRENDS AND TIMING Precipitation: Some mountain snow possible through the next 24hours. There will be a brief drier period tomorrow morning as the stronger front sets up its arrival. The timing is still under debate for Friday night or Saturday morning. Could see some mixed rain and snow tomorrow afternoon but it should be brief, if at all. Freezing levels: Freezing levels will rise to near or just above pass level by midday tomorrow but should drop back down below the pass level by 7pm. Freezing levels look to be in our favor for the weekend. Winds: Westerly flow will remain in place today with some gusty periods possible. There will be a brief east flow event tomorrow afternoon as the bigger system approaches the coast. Possible strong convergence winds on Saturday - will get a better feel for that in tomorrows model runs.