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FXUS63 KLBF 212308

Area Forecast Discussion
National Weather Service North Platte NE
508 PM CST Tue Nov 21 2017

.SHORT TERM...(This evening through Wednesday)
Issued at 324 PM CST Tue Nov 21 2017

Surface high pressure will settle south and be centered right
across the area this evening. Temperatures will quickly fall 
this evening as winds go calm and skies clear. As the surface high
moves off to the east after midnight, winds will shift to the 
south and temperatures will actually begin to rise. Westerly 
downslope winds take over Wednesday, with a rapid rise in 
temperatures during the morning, and highs topping out in the 
upper 50s and 60s by afternoon. Some high clouds will be around 
Wednesday, but doesn't appear to be thick enough to have much 
impact on high temperatures.

.LONG TERM...(Wednesday night through Tuesday)
Issued at 324 PM CST Tue Nov 21 2017

Well above-normal temperatures will prevail Thanksgiving Day and
Friday area-wide. Highs are then expected to remain above 
seasonable normal values through the remainder of long term 
period. Otherwise, scant chances for precipitation exist through 
Tuesday. Gusty winds are anticipated Friday, strongest across 
north central NEB. Of which, peak gusts up to 35-40 MPH are 
possible across parts of north central NEB. Lastly, another cold
frontal passage is expected late in the period prompting a cool 
down Tuesday.

Large scale pattern early Wednesday night features an upper-level
high centered over the Pacific offshore waters of southern CA and
Baja California with a ridge extending across British Columbia- 
Alberta. Elsewhere, northwest flow prevails overhead and a broad 
upper-level trough will be located over the eastern CONUS. The 
ridge will dominate upstream then brake down some beginning early 
Thursday as a shortwave trough tracks eastward over the top. The 
shortwave trough will move from the Pacific Northwest late 
Thursday through the Northern Plains by Friday. The pattern will
be conducive for dry conditions and above-normal temperatures 
Thursday and Friday. Westerly downsloping winds will persist 
Thursday with increasing temperatures aloft at low-levels. 850 
hPa temperatures are forecast to range from 12-16 C Thursday. For 
context, SPC Sounding climo at LBF shows the median temperature at
850 hPa for this time of year at around 4 C with a 90% moving 
average about 12 C. Current thinking is Thanksgiving Day will be 
the warmest day for much of the area with highs forecast in the 
mid 60s to near 70 F. A cold front is then expected to advance 
across the area later on Friday. Wherein some areas will see 
cooler highs than Thursday, albeit highs will remain above-normal.
Friday's highs are expected to range from the mid 50s in the 
northeast Panhandle to upper 60s towards south central NEB. The 
upper-level ridge is then expected to see amplification over the 
Western CONUS Friday. Conditions Friday are expected to be gusty,
especially across north central NEB with decent momentum transfer
anticipated. Mean mixed layer winds show potential for gusts to 
30-35 kts.

Beyond Friday, the upper-level ridge upstream in the western CONUS
will continue to affect the pattern through the weekend. While a 
modest drop in highs are expected Saturday attributable to the 
aforementioned cold frontal passage, highs will remain above 
seasonable normal values. Thereafter, another upper-level system
will prompt cooler highs Tuesday. 


.AVIATION...(For the 00Z TAFS through 00Z Wednesday evening)
Issued at 508 PM CST Tue Nov 21 2017

VFR conditions will occur the next 24 hours across western
Nebraska. Mainly few to scattered high cloudiness through Tuesday
afternoon. Winds will be light at 5 kts or less overnight, then
westerly up to 12 kts Tuesday afternoon.  



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