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NE OK/ NW AR/ SE KS/ SW MO Fall 2011


JoMo

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What the...

850mb frontogenesis... I don't know exactly what it is but the numbers are enormous. Keep in mind that the NWS typically would would want their contour maps to saturate, so they would make the contours go up to some really absurd value that they know will never happen. That donut hole in the middle is proof that the 850mb frontogenesis map saturates at a value of 1,000 (the inner circle has 1000 written on it).

Frontogenesis literally means "birth of a front" while frontolysis is the opposite. In a simple sense--all it means is an increasing thermal gradient with time over some horizontal distance. Typically it is measured in some form of temperature/[(distance)(time)]. A typical value may be Kelvin/[(km)(1 Hr)]. Frontogenesis can develop in a number of ways including low level convergence, horizontal deformation, tilting of the frontal boundary in the vertical, and diabatic heating. It is an atmospheric response to an imbalance--and the direct thermal circulation of a frontal zone is counteracted by processes that are simultaneously trying to balance the imbalance and weaken the front. A rapidly developing frontal zone (frontogenesis) shows the atmosphere is in a significant state of imbalance--typically in response to a developing strong divergent ageostrophic jet streak and/or a DPVA associated with an incoming shortwave/potential vorticity maximum. If there are high values of moisture in the low levels (theta-e) in the warm sector--latent heat release can further destabilize the low level environment and further strengthen both frontogenesis and low level convergence.

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Frontogenesis literally means "birth of a front" while frontolysis is the opposite. In a simple sense--all it means is an increasing thermal gradient with time over some horizontal distance. Typically it is measured in some form of temperature/[(distance)(time)]. A typical value may be Kelvin/[(km)(1 Hr)]. Frontogenesis can develop in a number of ways including low level convergence, horizontal deformation, tilting of the frontal boundary in the vertical, and diabatic heating. It is an atmospheric response to an imbalance--and the direct thermal circulation of a frontal zone is counteracted by processes that are simultaneously trying to balance the imbalance and weaken the front. A rapidly developing frontal zone (frontogenesis) shows the atmosphere is in a significant state of imbalance--typically in response to a developing strong divergent ageostrophic jet streak and/or a DPVA associated with an incoming shortwave/potential vorticity maximum. If there are high values of moisture in the low levels (theta-e) in the warm sector--latent heat release can further destabilize the low level environment and further strengthen both frontogenesis and low level convergence.

What kind of numbers do most storms show? I know it's definitely not 1,000+ like this one, but what is normal for a storm?

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Having been away all day, all I can say is that this is coming in much slower than the models suggested. (except the NAM)

Even a blind squirrel finds a nut every now and then.. It has been lowering QPF each run to come more in line with all the other models.

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What kind of numbers do most storms show? I know it's definitely not 1,000+ like this one, but what is normal for a storm?

I am not really sure what units SPC is using to calculate it. Based on the large numbers--it could very well be K/[(100km)(second)] where one second is (1/3600) of an hr. That is a guess--I am probably wrong.

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Local mets are pretty set on their snow totals... I hope they aren't all wrong.

Watching returns develop in NE OK... maybe they will saturate the atmosphere around here. Still very dry.

Yep, Joplinmet is going with 4-5" here. 3-4" down by you all I believe.

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I wanted to get the thoughts of everybody else on here, but I am thinking the area to watch for another swath of heavy snow accumulations in the next 4-6 hours is the area between highway 54/400 in southern Kansas (Dodge City-Wichita-Eureka) on the north and US Highway 64/412 on the south (Gage-Enid-Tulsa). Band of heavy snow has developed within the last 1-1.5 hours and has moved very little in this area. I am not sure if this is with the true arctic front, or if this might be the development SPC was talking about in their mesoscale discussion. The RUC and HRRR @ 22 and 23z have been a little south on where they intialized this area.

Meanwhile, just seen a report of 14.0" snow near Lehigh in Marion co, KS. My snow forecast is too low (which is a good thing).

PRELIMINARY LOCAL STORM REPORT

NATIONAL WEATHER SERVICE WICHITA KS

650 PM CST TUE FEB 08 2011

..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...

..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....

..REMARKS..

0648 PM HEAVY SNOW 3 SSW LEHIGH 38.33N 97.33W

02/08/2011 M14.0 INCH MARION KS TRAINED SPOTTER

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Local mets are pretty set on their snow totals... I hope they aren't all wrong.

Watching returns develop in NE OK... maybe they will saturate the atmosphere around here. Still very dry.

If the HRRR is correct there's gonna be a period of fairly heavy snow across this corner of MO early tomorrow. We may see some larger totals if these trends continue.

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PRELIMINARY LOCAL STORM REPORT

NATIONAL WEATHER SERVICE WICHITA KS

703 PM CST TUE FEB 08 2011

..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...

..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....

..REMARKS..

0640 PM HEAVY SNOW 1 E HOISINGTON 38.52N 98.76W

02/08/2011 M15.0 INCH BARTON KS TRAINED SPOTTER

When I was putting my snow forecast together this morning, I didn't think the projected snowfall would bust higher than my forecast. This is a very impressive storm to say the least......and the night is young.

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Hey guys, just pushed out fresh smartmodel runs for 01Z. Also looking at snowfall potential around the midwest, still tracking snow accumulation of around 8" in the Oklahoma City areas, 7" around the Tulsa region and out in W. OK another 4-6" inches of snow. Up in Kansas seeing an additional 1-3" for tonight to add to the impressive totals up there. Any thoughts or updates out there. You can view the data on the smartwxmodel site.

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between 14 and 15 inches of snow at my parents as of 6pm in McPherson

0600 PM HEAVY SNOW MCPHERSON 38.37N 97.66W

02/08/2011 M14.2 INCH MCPHERSON KS TRAINED SPOTTER

-since then my brother says they have had an inch or two

also holy crap

0720 PM HEAVY SNOW NEWTON 38.04N 97.34W

02/08/2011 E17.0 INCH HARVEY KS TRAINED SPOTTER

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