Area Forecast Discussion
Issued by NWS Greer, SC

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000 FXUS62 KGSP 240206 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 1006 PM EDT Sun Oct 23 2016 .SYNOPSIS... High pressure will remain across the area today before a dry cold front crosses through on Monday. Strong high pressure will quickly build back in from the north through the middle of the week...with another frontal passage expected late Thursday. && .NEAR TERM /THROUGH MONDAY/... As of 1000 PM...A quiet night on tap for the the forecast area as dry high pressure lingers across the Deep South. Clear conditions with light winds expected overnight. Low temperatures across the mtns will reflect an inverse lapse rate, ranging from around 40 within the valleys to the mid 40s across the ridges. A dry backdoor cold front is expected to slip southward across the NC foothills and Piedmont during the late morning to mid day period, passing across the upstate of SC during the early afternoon. Sfc winds will veer has the front approaches during the morning hours, becoming NW by mid day Monday. Only a few Cirrus clouds will be possible with the passage of the front. The timing of weak CAA in the wake of the front will favor mild high temperatures across the region. High temperatures are forecast to range from the low 80s across the upstate to the low 70s within the mtn valleys. RH values may rise only 5 percentages over values observed on Sunday. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... As of 215 PM Sunday, much of the short term will be characterized by a non or slowly-progressive pattern, with a long wave trough along, or just off the East Coast, and mean ridging across the central Conus. This will result in an expansive surface ridge associated with Canadian high pressure gradually build into the area through the period. Resultant (relatively) low thickness values/easterly component to the low level flow will result temps near to a little below climo through the period. Other than some occl cirrus (esp toward the end of the period, as a short wave trough ejects from the central Plains), skies should remain cloud-free. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... As of 215 pm EDT Sunday: Overall the extended is pretty quiet, but we`ll start the period with a shortwave pushing a front down the Mississippi Valley, approaching the Southern Appalachians Thursday morning. Of the operational models, the GFS is faster but all generally bring the front through sometime late Thursday. Moisture is fairly anemic and guidance seems to be pulling back on the southern edge of the moisture. The GFS has a little more precipitation ahead of the front, the ECMWF lingers it a little longer, but in the end we`re talking slight to low chance pops and storm-total generally less than 1/2". Expect a cloudy and cool day Thursday, and with winds swinging around to the northwest and the downsloping component, should actually see temperatures warmer Friday into the weekend despite being behind the cold front. Mass fields diverge between the operational models but looks like some sort of shortwave will pass through during the weekend, and have kept the slight chance pops that we had already advertised across the northern mountains Saturday night. Not enough model consistency late in the period to hang our hats on anything specific so just kept with a blend with slightly above-normal temperatures and continued dry. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... At KCLT and elsewhere: VFR conditions expected thru TAF period. A dry cold front will slide southward across the western Carolinas during the late morning to midday hours on Monday, passing to the south by early evening. With little moisture to work with, only a wind shift is expected with the fropa. Winds will shift from SW to W or WNW by midday, then veer further to NW Monday evening. Only a few wisps of cirrus will stream by from the west periodically through the period. A few stratocumulus may bank up against the western slopes of the Appalachians Monday afternoon, but shouldn`t impact any of the TAF sites. Outlook: Dry high pressure will persist over the Southeast through Wednesday. Then a fast-moving cold front will cross the area Thursday or Thursday night, but with limited moisture. Confidence Table... 02-08Z 08-14Z 14-20Z 20-00Z KCLT High 100% High 100% High 100% High 100% KGSP High 100% High 100% High 100% High 100% KAVL High 100% High 100% High 100% High 100% KHKY High 100% High 100% High 100% High 100% KGMU High 100% High 100% High 100% High 100% KAND High 100% High 100% High 100% High 100% The percentage reflects the number of guidance members agreeing with the scheduled TAF issuance flight rule category. Complete hourly experimental aviation forecast consistency tables and ensemble forecasts are available at the following link: && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...SBK NEAR TERM...ARK/NED SHORT TERM...JDL LONG TERM...TDP AVIATION...ARK is the U.S. government's official web portal to all federal, state and local government web resources and services.