wxgeek's weather-First Weather Outlook of 2014-Update 1/3

Update Fri Jan 3

Significant winter storm beginning to exit the east coast, but has left a mess in it's wake. Up to 2 feet of snow across the Northeast has snarled travel. Over 2000 flights cancelled, and many roads remain closed along with below zero temps. Here in CO, another very pleasant, albeit windy at times, day across the state. Our weather will take a dramatic turn tonight into the weekend. Cold front associated with a vigorous upper level trough will move into northern CO overnight, with snow developing behind front. Front should make it south to near US 50 by sunrise Saturday, with snow spreading south to the Palmer Divide so foothill residents likely to wake up to snow Saturday morning. Snow is expected to persist across most of the state during the day on Saturday and will be accompanied by gusty northerly winds which will create blowing and drifting of snow, especially in the High Country. Winter Storm Warning and Winter Weather Advisory covers nearly all of CO west of the Front Range Crest and Divide and are in effect from 5 pm Friday through 5 pm Saturday. Models have differing snow amounts, especially east of the Divide, with the GFS having much higher amounts than the NAM and the WRF in between. Given strong dynamic support aloft with strong jet stream, tending to favor the higher amounts, but heavier snowfall likely to be banded along jet stream, so highest amounts will be in these bands, and where those form is very hard to predict. This is not a classic upslope system, so areas of the plains may receive higher snow amounts than foothills. Here is my best guess for snow amounts:

Northern Mountains: 8-16 inches
Central and Southwest Mountains: 3-8 inches
Foothills and Palmer Divide: 2-6 inches
Urban Corridor and plains: 1-4 inches

Snow will diminish by Saturday evening, with some flurries persisting overnight into Sunday morning. Travel anywhere in CO Saturday could be difficult, especially across the mountains where delays and closures will be possible. Anyone traveling Saturday should be well prepared. By Sunday, CO will be on the western periphery of very cold arctic air mass that will begin to push south into the central U.S. Coldest air will be across the upper Midwest, so MN, WI, IA will see temps on Monday of -15 to -30 F with wind chills approaching -60F. This arctic air will push all the way to the Gulf Coast with freezing temps so citrus crops could be in danger. Arctic air will move east to the Northeast on Tuesday. Our system from Saturday will be on the eastern edge of the arctic air, so another winter storm will affect the Ohio Valley Sunday and into the Northeast on Monday.

CO will feel coldest temps Sunday into Monday morning, then temps will begin to warm Monday afternoon into Tuesday. Some mountain snow will be possible Wednesday into Friday next week, but foothills and plains should remain dry. For next weekend, conditions look dry and mild, so Broncos home game should be played in very nice weather before next system brings a chance for snow statewide on Monday.

_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

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Update Thu Jan 2

Beautiful day across the state today. Mountain wave beginning to form alonf the Front Range, so winds will pick up from this afternoon through the night and into Friday evening. Westerly winds speeds of 20-45 mph likely with gusts to 60 mph in favored areas of the foothills. Upstream system looking a tad stronger on latest model runs, which has prompted the NWS to issue a Winter Storm Warning for the northern mountains and Winter Weather Advisory for the central mountains from 9 pm Fri through 9 am Sunday. Snow amounts of 8-16 inches for the northern mountains and 3-7 inches for the central mountains possible. Cold front will move south into northern CO Friday night and south across the state during the day on Saturday. Snow will develop behind front, with snow developing Saturday morning for the foothills and Urban Corridor north of the Palmer Divide, and move south Saturday afternoon. Snow likely to persist into Saturday evening with some flurries possible into Sunday morning. For the foothills, we could see 1-4 inches of snow, with 1/2 to 3 inches for the Urban Corridor and plains. Sunday will remain cool as arctic air mass begins to push south into the central U.S.

Arctic front will push into eastern CO Sunday night with arctic air pushing west to the foothills. Low clouds with some light snow possible Sunday night into Monday morning from the foothills east. Coldest temps will be on the far eastern plains, but we will still feel arctic air into the foothills on Monday. Temps will begin to moderate by Tuesday under mostly sunny skies statewide. Some mountain snow possible on Wednesday, but other than that temps look mild and dry conditions statewide through next weekend. In general, models keep upper ridge along the west coast through this weekend, then move it slightly farther east into the Great Basin next week and beyond, which spells dry conditions for most of CO through mid to late January.

Good snowstorm ongoing across the mid Atlantic and Northeast that will continue into Friday morning, so some travel issues likely in this region. Aforementioned arctic air mass will bring frigid temps to much of the central and eastern U.S. early next week with temps of -20 to -40 F possible across the upper midwest and Great Lakes.

For football weather, still looks nice in Phily on Saturday, Indy is inside. Sunday games look nasty. Snow for the entire game in Cincinnati on Sunday, and arctic air in Green Bay Sunday. Temp at kickoff in Green Bay will be near zero with a wind chill of -20F, and by the end of the game temp will be near -10F with wind chill of -30F. For those wondering, not even close to record cold for football. Coldest games, depending on whether you use ambient temp or wind chill, would be the famous Ice Bowl in Green Bay on Dec 31, 1967 where the ambient temp was -13F and wind chill was -48F, and a playoff game in Cincinnati on Jan 10, 1982 where the temp was -9F with a wind chill of -59F. Actually pretty dangerous to be outside in that weather. I remember watching both those games on TV and recall the suffering, especially Dan Fouts of San Diego in the game in Cincinnati. I recall interviws with Don Meredith of Dallas in the Green Bay game stating his face was so numb, players couldn't understand the plays he was calling in the huddle.

_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

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Happy New Year to all. Hopefully a time to reflect on the past year and to look forward to a new year.

The New Year is starting off with a blast of snow to many areas of CO. Mountains have received 2-8 inches past 24 hours, and snow will continue much of the day and diminish this evening. Tough travel in the mountains with strong northwest winds accompanying snow. Winter Weather Advisory remain in effect through Noon today. Farther east, mostly a dusting in the foothills, with some snow moving across the plains at this time. Flurries likely to continue into this afternoon then diminish by this evening. Thursday looks to be mostly sunny and mild statewide.

Next system from the northwest will move into CO late Friday into Saturday. Ahead of this system, gusty westerly winds expected to develop along the foothills and adjacent plains Thuraday night into Friday afternoon with speeds of 20-45 mph and gusts to 60 mph possible. Cold front will move into CO Friday night with snow developing behind front across northern CO then move south by Saturday morning. System looks similar to system that moved across CO New Years Day, so expecting 3-7 inches for the mountains, with a trace to 2 inches for the foothills and Urban Corridor and plains. Snow should diminish by Saturday evening with a few flurries lingering into Sunday morning. Temps will be much cooler Saturday and Sunday.

For next week, models suggesting we will see an arctic intrusion associated with a large arctic air mass moving south into the central U.S. early next week. CO will be on the western periphery of this air mass, so arctic air should push west up against foothills, but does not look to make it west of the Divide. Coldest air will be on the esatern plains with temps near zero along the KS border on Monday. Easterly upslope flow will accompany this push of arctic air, so expect low clouds over the plains that push into the foothills, with some light snow and possible freezing drizzle Monday. Arctic air moves east Tuesday, so temps will begin to moderate across eastern CO Tuesday, with further warming Wednesday, as snow moves into western CO. Upper pattern is expected to persist with upper ridge along the west coast and upper trough over the eastern U.S. through the middle of January. This implies weather across CO will remain much like it was in December, with northwest flow aloft and system from the northwest skirting across the state, bringing some mountain snow, with little snow east of the Divide, and breezy to windy conditions along the foothills.

For the rest of the country, system today will move east into the Central Plains bringing snow, and will combine with moisture along the Gulf Coast on Thursday, to create a significant winter storm for much of the Ohio Valley, Mid Atlantic region and Northeast that will exit the east coast on Friday. Travel delays likely on Thursday with flight cancellations possible over the busy Northeast corridor. For next week, the aforementioned arctic blast will create very cold temps for much of the central and eastern U.S. early next week with parts of the upper Mississippi Valley and Great Lakes seeing temps of -20 to -40 F. This arctic blast also will bring freezing temps all the way to the Gulf Coast next week. Temps will moderate by late next week as another winter storm moves into the region.

For NFL fans, weather for playoff games this weekend looks as follows:

Saturday in Philadelphia weather looks nice, mostly sunny with temps in the mid to upper 20's.

Sunday in Cinncinati weather looks pretty nasty. Snow is likely with temps in the upper 20's to low 30's during the game. Accumulating snow of 1-3 inches possible during the game.

Sunday in Green Bay weather looks clear but very cold. Temps during the game likely to be in single digits, with westerly winds of 5-15 mph, wind chill values will be well below zero.

_________________
"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".

Bump for Jan 2 update

Bump for Jan 3 update