Marine Weather and Tides
10/9/2019 Updated the Marine Zones.
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|Sunrise 7:29AM||Sunset 5:23PM||Monday December 16, 2019 9:15 AM EST (14:15 UTC)||Moonrise 10:09PM||Moonset 11:20AM||Illumination 77%|
7 Day Forecast for Marine Location Near Lowndesville, SCHourly EDIT Help
Area Discussion for - Greenville-Spartanburg, SC  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS62 KGSP 161131 AFDGSP
Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 631 AM EST Mon Dec 16 2019
SYNOPSIS. A cold front with widespread rain is expected to arrive by Tuesday. High pressure will bring a return to near normal temperatures and dry conditions for the middle part of the week. Model guidance hints at a storm system this weekend, but there continues to be large differences between model guidance on the forecast weather.
NEAR TERM /THROUGH TONIGHT/. 600 AM Update . Low StCu continues to spread across the FA from the SW . while precip associated with frontal forcing remains well to the west over central TN into KY. Still expect periods of light pre/frontal isent lift -shra across the srn BR with minor accums thru the next update.
Atlantic ridging continues to dominate the pattern over the FA this morning while a good amt of llvl GOM moisture spreads in from the southwest. An h85 inversion has trapped this moisture and StCu allowing continued sfc mixing within negligible rad cooling. Thus . temps are running a little abv the fcst curve and are nearly steady-state while bumping up and down abv normal levels.
Cloud cover will remain high this afternoon . however good sw/ly flow and waa will allow temps to reach the lower to mid 60s over most locales Meanwhile. an active cold front will slowly advance toward the NC mtns and begin producing light rainfall across the far sw/rn BL arnd noon. Expect little rainfall amts thru the daytime period and it wont be until aft 04z or so when the higher precip rates associated with frontal forcing set up across the srn mtns. The front will slow down and align sw-ne aft 06z . which will allow for decent accums across the far srn BL thru 12z. Wont require a flood watch . but extreme sw/rn Graham and Macon counties could receive localized amts near 2 inches leading to minor hydro issues. Winds across the NC mtns will also increase with the frontal passage and likely die down by daybreak. Cross sections at KAVL show a 50+ kt llvl jet quickly descending to arnd 4000 ft aft 06z and weakening by daybreak So. have issued a wind adv for elevations abv 3500 feet beginning at 00z and ending at 12z Tue. All locales will see beneficial precip during the overnight with arnd an inch over the NE GA / western Upstate areas and abt a half an inch over the fthills and Piedmont regions. Soundings continue to indicate a high amt of bulk shear . arnd 60 kts aft 06z . while hodos lengthen yet remain rather straight-lined. Instability will be lacking (arnd 100-200 J/kg) . thus anticipate isol general thunder limited to the far sw/rn zones . which is in line with the SPC Day1 Outlook. The BL will remain well mixed overnight . so min temps will once again remain well abv normal with readings in the low to mid 50s.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/. As of 220 AM EST Monday: Positively tilted upper trough approaches the area Tuesday and crosses the area Tuesday night. This trough pushes a cold front across the area Tuesday. The system is quite dynamic with lots of forcing. However, there is little in the way of instability. That said, there will be enough CAPE for isolated storms along and south of the I-85 corridor. There will be quite a bit of shear and helicity ahead of the front, but the lack of instability will keep any severe chances very low. The best instability occurring in the morning is also a limiting factor. Of course, we'll have to keep an eye on this as it develops. Heavy rainfall is also expected during the morning, mainly over NE GA and the western Upstate. Currently don't expect any widespread flooding but isolated flooding will be possible.
Precip quickly moves east with the front during the afternoon. However, lingering moisture and developing NW flow will keep precip across the mountains into the evening. Good CAA develops behind the front which will help change the rain to snow across the higher elevations. Snow levels may drop to the valleys before precip ends around midnight. Given the short duration and generally high snow elevations, don't expect any significant accums. Could see up to an inch in the usual locations above 5000 feet. Gusty winds ahead of the front turn NW behind it. However, gusts look to remain below advisory levels with guidance keeping H85 winds below 50 knots. Gusty winds are expected outside of the mountains as well but mainly in the breezy range. Highs Tuesday will be 10 to 15 degrees above normal, even with an early high across the mountains. Lows Tuesday night will be near normal.
High pressure only slowly builds in from the northwest Wednesday and Wednesday night. This keeps a tight pressure gradient across the area Wednesday which relaxes Wednesday night. Gusty winds and some clouds will remain across the mountains with low end gusts during the day and clear skies elsewhere. Highs Wednesday will be 5 to 10 degrees below normal with lows Wednesday night around 5 degrees below normal.
LONG TERM /THURSDAY THROUGH SUNDAY/. As of 320 AM EST Monday: Low confidence forecast for this period as the guidance continues to show run to run inconsistency. That said, the GFS and Canadian have trended toward each other with a faster, weaker weekend system with cyclogenesis taking place along the SE Atlantic coast. The ECMWF remains stronger and slower with cyclogenesis taking place in the Gulf of Mexico with the low crossing south Florida.
The GFS and ECMWF start with a phased northern and southern stream; however, the GFS keeps the streams phased as the waves quickly move east and off shore. The ECMWF has a faster northern stream which splits off from the southern stream wave which then closes off into an upper low which slowly crosses the Gulf Coast and Florida.
The guidance agrees that Thursday will be near to 5 degrees below normal with temps rising to near normal Friday. Both days look to be dry. The GFS then brings moisture into the area Friday night which moves east Saturday as a surface low develops off the SE coast and quickly moves east. The ECMWF also brings moisture in but from the west Friday night and spreads it across the area Saturday. Moisture lingers Saturday night then diminishes Sunday as the its low develops in the Gulf of Mexico and crosses Florida. The GEFS mean is not as fast with more precip than the operational GFS. Therefore, have gone with PoP timing closer to the ECMWF but limited to slight chance given the uncertainty. Temps would be cold enough to indicate some snow potential; however, the uncertainty means chances are quite low. Do not expect any significant wintry precip for now.
AVIATION /12Z MONDAY THROUGH FRIDAY/. At KCLT and Elsewhere: An active weather pattern will affect all TAF sites thru the period. Expect a slow lowering cloud trend during the daytime period with MVFR CIGS at KAVL this morning as pre/frontal rain moves in from the west. Lowering CIGS to IFR is possible by mid afternoon across the NC mtn valleys and fthills. Visibility will remain mostly VFR with MVFR/IFR restrictions expected within precip later this evening thru the period. The rainfall will become more widespread late in the period with all sites receiving -shra and IFR/LIFR conds to end the period.
Outlook: Moisture will remain high across the area associated with a cold front into Tuesday. The front will bring a round of rain showers, with cig/vis restrictions likely into the afternoon and evening. Drier air and strong high pressure will set up by midweek.
Confidence Table .
11-17Z 17-23Z 23-05Z 05-06Z KCLT High 94% High 100% High 95% High 83% KGSP High 89% Med 75% High 95% Low 41% KAVL High 83% High 100% Med 75% High 83% KHKY Med 78% High 90% High 95% Med 78% KGMU High 89% Med 75% High 95% Low 47% KAND Med 78% High 85% High 95% Med 69%
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 . Wind Advisory above 3500 feet from 7 PM this evening to 7 AM EST Tuesday for NCZ051-052-058-059-062>064. SC . None.
SYNOPSIS . RWH NEAR TERM . SBK SHORT TERM . RWH LONG TERM . RWH AVIATION . SBK
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|CHDS1 - Strom Thurmond Dam, SC||46 mi||55 min||S 1.9 G 5.1||43°F|
|LMFS1 - Lake Murray SC||74 mi||115 min||S 5.1 G 6||54°F|
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.
|Anderson, Anderson County Airport, SC||18 mi||79 min||S 5||10.00 mi||Overcast||50°F||46°F||89%||1022 hPa|
Link to 5 minute data for KAND
Wind History from AND (wind in knots)
|1 day ago||W|
|2 days ago||E||NE||NE|
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NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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Wind Forecast for Greenville-Spartanburg, SC (9,2,3,4)(on/off)  Help
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