Winter Storm Watch for Seattle and all of western WA
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Its down right balmy today as we are at a whopping 34.4 degrees, nothing melting yet though with the dewpoint still below freezing.
1/10/05 LK Goodwin WA
12:51:41 AM CURRENT
Partly Cloudy
Temperature (ºF) 34.4
Humidity (%) 78.1
Wind (mph) NW 1.1
Daily Rain (") 0.00 No
Pressure ("Hg) 30.02
Dew Point: 31.0 ºF
Snow Depth 1.5"
1/10/05 LK Goodwin WA
12:51:41 AM CURRENT
Partly Cloudy
Temperature (ºF) 34.4
Humidity (%) 78.1
Wind (mph) NW 1.1
Daily Rain (") 0.00 No
Pressure ("Hg) 30.02
Dew Point: 31.0 ºF
Snow Depth 1.5"
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This forecast has some serious high-bust potential. I noticed that the local guys are just trying to ignore it for now!!
I told my wife... we may get a foot of snow tomorrow night or we may get nothing at all. She laughed and said thanks for the useful information!! But its true. It will be very difficult to determine until it happens.
You are close to the Puget Sound but a little further north than the usual rain-shadow. I would guess 2-4 inches there but it could be 10 inches or it could be nothing. Very frustrating.
And then the 18Z run of the ETA trends warmer!! Its tough enough to determine how much snow even if the models forecast the upper air pattern perfectly... let alone all the model changes each run.
I told my wife... we may get a foot of snow tomorrow night or we may get nothing at all. She laughed and said thanks for the useful information!! But its true. It will be very difficult to determine until it happens.
You are close to the Puget Sound but a little further north than the usual rain-shadow. I would guess 2-4 inches there but it could be 10 inches or it could be nothing. Very frustrating.
And then the 18Z run of the ETA trends warmer!! Its tough enough to determine how much snow even if the models forecast the upper air pattern perfectly... let alone all the model changes each run.
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Like TT-SEA said, this has high potential but definitely no certainty. In these situations, one place might get hammered with 6 inches of snow...but 20 miles away, there's nothing. It all depends on the strength/location of the PSCZ. Remember, even if the snow level is at 500-1000 feet, the PSCZ can drag colder air down from higher altitudes and bring the snow down to sea level. The latest ETA is a little warmer, but not enough to shift the overall pattern. I'm not sure how much you'll get R-Dub...but you probably will escape most of the Olympic rainshadow...should be from Everett south to about Olympia. Initially, everything should be rain...except Whatcom county with trapped cold air. But once the front passes and 500 mb thicknesses start to drop and a PSCZ forms, things could get interesting. Remember, this is not a definite thing...if the PSCZ doesn't form, most likely no one will see anything. And the windstorm has potential, but definitely not certainty. With a similar windstorm back in October of 2003, Mukilteo/Whidbey Island got hammered with wind gusts of 65 mph. But for this thing to play out, many things have to come together...a strong low-level, high-level westerly flow roaring down the Strait of Juan Defuca, strong cold air advection behind the passing cold front and a surface low that tracks east into Eastern Washington. It's a very localized event but has tremendous "punch." Something to bear watching.
Anthony
Anthony
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I don't know what to think of the latest NWS forecast. Doesn't sound like they have a clue either. They also say places will be cold tonight that has snow cover.....Places like Bellingham, there are many other places that have snow cover. Seems like if its not happening in seattle, its not happening anywhere besides the boarder. They don't even mention cold temps after the system passes by. SHEESSH!!!
Already down to 30.8 degrees here, but according to NWS it won't be cold here, just Bellingham.
Already down to 30.8 degrees here, but according to NWS it won't be cold here, just Bellingham.
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Felton and Kam do very broad weather discussions. They don't get into specifics and tend to favor a warmer/drier bias. I find it funny that Felton doesn't even mention the possibility of a localized high wind event for Whidbey Island/Everett area. There's the high possibility of this happening. I guess we'll have to wait until the evening discussion...hopefully that's more specific and gives more information. He didn't even mention the possibility for snow in Bellingham where the temperature will be below freezing for most of Tuesday. The two good meteorologists are Burke and Mercer. They always give good information and sound optimistic. I'll have to wait until Scott Sistek updates his Komo 4 discussion around 4pm. Until then, it's back to homework. Oh yeah, it's dropped 7 degrees since 1pm this afternoon...back down to 33 F. Another hard freeze tonight...overnight lows from 20-25 F.
Anthony
Anthony
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Latest NWS Forecast Discussion:
.DISCUSSION...SATELLITE IMAGERY SHOWS VORT MAX MOVING INTO NORTHERN
CALIFORNIA. COLD FRONT DROPPING DOWN BRITISH COLUMBIA COAST NEAR THE
QUEEN CHARLOTTES AT 22Z. PARTLY CLOUDY SKIES OVER WESTERN
WASHINGTON. THESE CONDITIONS WILL CONTINUE OVERNIGHT WHICH WILL LEAD
TO SOME COOL LOW TEMPERATURES IN AREAS WITH SNOW ON THE GROUND LIKE
BELLINGHAM. COLD FRONT MOVING THROUGH WESTERN WASHINGTON 03Z-09Z
WEDNESDAY. GOOD CAA BEHIND THE FRONT. CONDITIONS SETTING UP FOR A
STRONG PUGET SOUND CONVERGENCE ZONE WITH MODEL 850 MB WINDS PARALLEL
TO THE STRAIT AT 40 KNOTS. GOOD OROGRAPHICS RIGHT AHEAD AND WITH
THE FRONT BRINGING SNOW TO THE MOUNTAINS. BEHIND THE FRONT BEST SNOW
FOR THE MOUNTAINS FOCUSED IN THE CONVERGENCE ZONE BETWEEN STEVENS
AND SNOQUALMIE PASS. FOR THE LOWLANDS STRONG ONSHORE FLOW WILL KEEP
TEMPERATURES WARM ENOUGH TO KEEP SNOW OUT OF THE FORECAST. THE
EXCEPTION TO THIS WILL BE WITHIN THE CONVERGENCE ZONE WHERE THE
CONVECTIVE PRECIPITATION WILL PUSH THE SNOW LEVEL DOWN TO THE
SURFACE. SO THE QUESTION IS WHERE WILL THE CONVERGENCE ZONE SET UP.
AT THIS TIME WITH THE 850 MB WINDS WEST NORTHWESTERLY IT LOOKS LIKE
THE CONVERGENCE ZONE WILL SET UP SOUTH OF EVERETT BUT NORTH OF
DOWNTOWN SEATTLE. WITH THE STRONG FLOW ALOFT THERE IS THE
POSSIBILITY OF THE CONVERGENCE ZONE GETTING PUSHED INTO THE CASCADES
BYPASSING MOST OF THE METRO AREA. WILL NOT GO OUT WITH ANY HEADLINES
FOR THE LOWLANDS SINCE IT IS STILL TOO EARLY TO REALLY PIN DOWN
WHERE THE CONVERGENCE IS GOING TO SET UP. FOR THE MOUNTAINS WILL
CONTINUE WINTER STORM WATCH FOR LATER TUESDAY NIGHT AND EXTENDED THE
WATCH INTO WEDNESDAY MORNING TO ACCOUNT FOR THE CONVERGENCE.
CONDITIONS DRY OUT AS THE DAY WEARS ON WEDNESDAY WITH ANOTHER HIGH
BUILDING OVER SOUTHERN BRITISH COLUMBIA AND THE LOW LEVEL FLOW
TURNING OFFSHORE. OFFSHORE FLOW CONTINUES INTO THURSDAY FOR ANOTHER
DRY DAY.
.EXTENDED...GOOD CONSISTENCY AMONG THE EXTENDED MODELS WITH AN UPPER
LEVEL RIDGE OFFSHORE SLOWLY WEAKENING THROUGH THE EXTENDED PERIOD.
18Z GFS THROWS A WRINKLE INTO THE SCENARIO WITH THE FRONT THAT
STALLS OFF THE COAST FOR THE WEEKEND MOVING INLAND. FOR NOW WILL
STAY WITH THE CONSENSUS OF A DRY FORECAST FOR THE EXTENDED PERIOD.
FELTON
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Article posted by Scott Sistek on Komo4.com:
SEATTLE - If you were to look up "Seattle Snowstorm" in the various weather textbooks, you'd find it talks about arctic air coming down from the north, meeting with a moist warm weather system coming in off the Pacific Ocean, and all that rain falling into the arctic air and turning to snow. Sounds simple, doesn't it?
Well, apparently Mother Nature doesn't have that textbook. Or, perhaps she's considering writing some new chapters.
We once again have another challenging and somewhat unique weather scenario playing out that, if it goes according to computer forecasting model plan, could bring a return to the snow to some areas of the Puget Sound area.
I know, I'm with ya. After the past week, you're ready to punt those mind-changing why-can't-they-ever-get-it-completely-right computer forecasting models into the Puget Sound, or, at least subject them to watching the bad auditions on American Idol.
But, the models are right more times than you think, and when they're all kind of singing the same tune, you have to take notice (even if Simon Cowell doesn't).
So, the latest forecasting model snow scenario du jour shows an area of low pressure once again developing up in southeastern Alaska and sliding south/southeast through British Columbia Tuesday and then turning to the east around the Washington/B.C. border near the Okanogan Mountains Tuesday night, dragging an arctic front behind it as it comes along. This would likely begin as increasing clouds late Tuesday, with rain developing first Tuesday evening before we cool off and get into the fun stuff.
The potential scenario presents three weather challenges (well, three-and-a-half) for those that live around here.
One: The Wind
The first is the wind. Depending on the strength and position of the low (and the models have it in a pretty good position), that low could draw down some strong westerly winds down the Strait of Juan de Fuca, barrel over Whidbey Island and Admiralty Inlet, then blow through the greater Everett area before crashing into the Cascades. Right now, wind speeds look to be in the 25-40 mph range, with perhaps higher gusts. (So, it's windy with a twist. Instead of those frigid easterly Fraser Winds of the past few days, we'll have strong west winds.)
One (and a half): Colder Air
That front is also going to drag in some colder air behind it. Not too cold, but we don't need to get much colder to get back to the snow line.
Two: A Convergence Zone +Foothill Snow
As that front passes and the Strait winds die down a tad, we're looking at pretty favorable (OK, textbook) conditions for a very strong convergence zone. Combine strong convergence zones with cool air near freezing, and you've got the recipe for some snow. This would be a somewhat-localized area of a line from Shoreline to North Everett stretching east to the Cascades.
Forecasting snow totals right now would be fruitless, since they'd be sure to change. But I saw one National Weather Service forecaster term it: "anything could happen from the sublime to the ridiculous." So, even though the snow flag is likely battered from overuse, we're raising it again for the Convergence Zone areas Tuesday night. (Yes, this means Everett could be in the double whammy of gusty winds and snow.)
The heavier accumulations would be in the Snohomish County foothills and -- to a lesser extent -- the King County foothills.
A WINTER STORM WATCH is in effect for that area Tuesday night. The WATCH says 2-4" in the central Cascade foothills are possible (remember, a WATCH means conditions are right, but not certain. A WARNING would mean it's no doubt coming, or is already happening.), with the potential for 6+" in the Convergence Zone foothill areas of Snohomish Counties. (But remember, I'm not forecasting snow totals)
Three: Mountain Snow
With all that wind crashing into the Cascades, then ramping up the hills and squeezing out their moisture, skiers finally -- FINALLY -- FINALLY! -- have a recipe for a good ol' fashioned mountain snow storm. A WINTER STORM WATCH is in effect for the mountains too for Tuesday night. Here, we're looking for at least a foot of new snow. But on the flip side, this will make pass travel dangerous -- especially Snoqualmie and Stevens. With the heavy snows comes the strong winds and blowing snow, so Tuesday night is not a good time to be crossing the mountains.
Four: Elsewhere (Hey, look, I can be a miscalculating computer model too!)
For the rest of the area, including the Downtown Seattle/Bellevue/Tacoma areas and other points outside the Convergence Zone, we're looking at perhaps rain changing to snow Tuesday night as that colder air moves in, but we won't have as much moisture here. So not looking at any significant accumulations -- yet.
If this sounds complex and like a lot of things have to mix together just right for this to happen, you’re right. It’s like walking the weather tightrope – one little change could knock this forecast off the wire. (Maybe I can make one of those "small print" paragraphs standard here about how these models can change and how they're not valid in Vermont and don't require a purchase and the like...) Anyway, we'll keep track of it.
Some snow lingers into Wednesday morning before we dry out and get sunny for the rest of the week. (Skiers, Thursday and Friday might be the best skiing conditions you've seen in AGES!)
In the meantime, I'm taking Mother Nature's pen away. We've seen enough crazy snow scenarios for one winter![]()
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