Area Forecast Discussion
Issued by NWS Knoxville/Tri Cities, TN

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000 FXUS64 KMRX 241916 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 316 PM EDT Fri Mar 24 2017 .SHORT TERM...(Tonight through tomorrow)...Expect some cloud cover to linger overnight but also with patches of partial clearing across the area. With lingering clouds and continued southerly flow lows will be quite mild. Temps will generally be in the upper 40s to low to mid 50s, which is around 10 to 15 degrees above normal. High pressure that has been to our east will gradually shift further east tomorrow in advance of an incoming low pressure system. Incoming low and high still to our east will further ramp up heights increasing max temps by another few degrees. Temps in the lower 70s expected at most locations, which will be around 5 to 10 degrees above normal. This system is rather slow to move in due to the amount of dry air in place out ahead of it. Will keep areas north of I-40 dry through the day. By mid afternoon start introducing pops south of I-40 and slowly increase them through the rest of the afternoon. Bulk of the precip is expected to move in after this short-term period. With the tightening pressure gradient expecting winds to be gusty tomorrow with gusts generally ranging from 10 to 15 mph with some gusts up to 20 mph. Expect party sunny conditions for the most part, with clouds around the area along with peaks of sunshine. .LONG TERM...Saturday night through Friday)...Overall...expect a rather unsettled weather pattern throughout the extended. While there are some discrepancies, as expected, between models, they are in relatively good agreement through about Tuesday. A cold front will approach the area Saturday night into Sunday. With weak instability and decent 850mb winds, there will be a chance for some thunderstorms overnight Saturday. Daytime heating on Sunday will help to further destabilize the environment with forecast afternoon SBCAPE values of 500-1000 J/kg, and when combined with dewpoints in the upper 50s and forecast 0-6km shear values of 20-30kts, this should be enough to trigger isolated to scattered thunderstorms. At this point, SPC has our forecast area outlooked for a marginal risk of severe storms for Sunday, with the main concerns being isolated damaging winds and potentially some hail with the strongest updrafts. This system pulls away from the area Sunday night, but we will have only a brief break in rain chances before the next system moves in for Monday/Tuesday. A weak shortwave will push east from the Great Plains on Monday, bringing another round of showers and potentially some thunderstorms to the area. Wednesday and Thursday look like potentially the driest days of the week, with weak ridging overhead as another system for late week digs into south-central US and strengthens. A warm frontal boundary associated with this closed low will approach the area late Thursday, and will serve as a focus for showers and thunderstorms on Friday. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 56 73 57 72 / 0 40 100 70 Knoxville McGhee Tyson Airport, TN 53 73 56 71 / 0 10 90 70 Oak Ridge, TN 52 73 55 71 / 0 10 100 70 Tri Cities Airport, TN 49 73 51 69 / 0 10 70 70 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...None. TN...None. VA...None. && $$ SR/EMH

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