Marine Weather and Tides
12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed.
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.
|Sunrise 7:27AM||Sunset 5:42PM||Thursday January 23, 2020 6:31 AM EST (11:31 UTC)||Moonrise 6:38AM||Moonset 4:36PM||Illumination 3%|
7 Day Forecast for Marine Location Near Lake Norman of Catawba, NCHourly EDIT Help
Area Discussion for - Greenville-Spartanburg, SC  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS62 KGSP 230842 AFDGSP
Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 342 AM EST Thu Jan 23 2020
SYNOPSIS. Slowly moderating Canadian high pressure will remain over the area today. A cold front will then cross the area Friday night bringing mostly rain. Seasonal high pressure slowly builds through next week.
NEAR TERM /THROUGH TONIGHT/. As of 300 AM EST: A thickening high-based broken to overcast sky is expected across the forecast area today, as plenty of cloud cover can be seen upstream on IR satellite imagery and METARs across the Southeast. These clouds are in response to height falls with an approaching upper low swinging into the Midwest. An occluded low pressure system associated with the upper low will increase slowly increase deep-layer southerly to southwesterly flow atop the forecast area (FA). Forecast soundings show gradual moistening from the top down, with limited low-level moisture for any precip thru the daylight hours today. Guidance generally agrees on some leading edge -RA breaking out in the western tier of counties from the Smokies to the northeast GA counties by the end of the day. But overall, the day should be dry with temps held just below normal by the increasing cloud cover and a lingering cool sfc ridge extending from high pressure to our NE.
Precip should rapidly expand in coverage from west to east across the forecast area this evening with categorical PoPs nearly everywhere by daybreak Friday. There is still some concern that the initially dry boundary layer may wet-bulb temps down below freezing across portions of the NC mountains as precip increases in intensity. However, confidence on any widespread areas getting locked in with several hours of freezing rain is still low. The low-level jet (LLJ) associated with an approaching cold front will be SELY with a really good upslope component along the Escarpment tonight. This will enhance rainfall totals, especially in the southern mountains of NC (which may get 1-2" of QPF by 12z Friday). With all that said, even going with the 25% percentile on min temps tonight only results in pockets of 30-32 deg temps, which start warming before daybreak Friday. The strong WAA looks to overwhelm any sub-freezing temps within an in-situ wedge. So will hold off on any winter weather advisory for ice accums. But depending on trends, the day shift may need to issue one for portions of NC near the escarpment. For now, will advertise a brief mention of freezing rain and light ice accums in the grids in the usual cold spots of the Upper French Broad Valley and the eastern Escarpment of NC. But overall, it will be a cold rain tonight with lows in the mid to upper 30s. One other concern with the SELY LLJ will be gusty winds on the highest peaks. At this point, the LLJ is only 40-50 kt, and with strong WAA, we usually don't see gusts below about 5000 ft in these setups. So no wind advisory will be issued for now.
SHORT TERM /FRIDAY THROUGH SUNDAY/. As of 325 AM Thursday: Precip will be ongoing across the CWFA at the start of the period. Temps should have warmed enough that precip should be all rain by this time. That said, can't rule out a lingering wintry mix for a couple of hours after daybreak across the higher elevations of the northern mountains. Since the wedge is quite weak, the guidance has now all come in with some instability, generally along and south of the I-85 corridor, as triple point low forms along the front as it moves east across the area. Despite the strong shear and helicity associated with this, the instability looks to be weak enough for just some rumbles of thunder and little to no chance of severe storms. The dry slot behind the front quickly works into the area from late afternoon into early evening bringing an end to the precip outside of the mountains. With the strong forcing and PW values one standard deviation above normal, QPF is expected to range from 1 to 2 inches, with 3 inch amounts along and near the southern escarpment upslope areas. Given that much of this will fall during a 12-18 hour period, isolated flooding will be possible. Windy to breezy conditions are expected.
A dry and breezy to windy forecast continues Saturday through Sunday for all but the NW flow precip locations along and near the TN border. While it looks to be a relatively prolonged period of NW flow snow, the guidance doesn't agree on if the snowfall amounts will be significant. The wind speeds and directions and the CAA are good but not great. However, there area multiple short waves dropping through the flow across the area and weak low level instability which are favorable. Keep low PoP across the usual areas through the period and will have to keep an eye on the situation for any potentially significant snowfall.
Temps Friday will be near to even below normal under the heart of the eroding wedge with above normal amounts east and south. Highs Saturday and Sunday will be below normal over the mountains and near normal elsewhere. Lows will bounce around near or a little below normal.
LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/. As of 330 AM Thursday: Guidance now agrees in a generally dry forecast in association with a clipper-like wave Monday as it is south of the area near the Gulf Coast. Dry high pressure builds in on Tuesday then precip chances return Wednesday as another frontal system approaches from the west. Highs and lows rise up to 5 degrees above normal through the period.
AVIATION /09Z THURSDAY THROUGH MONDAY/. At KCLT and elsewhere: Cirrus will continue to drift in from the west thru this morning, lowering and thickening thru the day today with the approach of a cold front. Forecast soundings show rapid moistening of the lower levels this evening, with cigs expected to be low VFR, then MVFR by end of the 06z TAF period. Light rain should start breaking out toward the end of the period, so have PROB30 in there for now. Winds will remain light thru the period out of the NE (except SE at KAVL).
Outlook: Low cigs, restricted vsby and precip will spread into the area late tonight thru Friday morning ahead of an approaching front. The front will cross the area Friday night, clearing out the restrictions (except possibly lingering into Saturday at KAVL within NWLY flow). After that, dry conditions will persist through the weekend and early next week.
Confidence Table .
08-14Z 14-20Z 20-02Z 02-06Z KCLT High 100% High 100% High 100% High 92% KGSP High 100% High 100% High 100% Med 72% KAVL High 100% High 100% High 100% High 86% KHKY High 100% High 100% High 100% High 100% KGMU High 100% High 100% High 100% Med 68% KAND High 100% High 100% High 100% 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 . None. SC . None.
SYNOPSIS . RWH NEAR TERM . ARK SHORT TERM . RWH LONG TERM . RWH AVIATION . ARK
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|
|WATS1 - Lake Wateree, SC||89 mi||62 min||NNE 2.9 G 8||36°F|
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.
Link to 5 minute data for KSVH
Wind History from SVH (wind in knots)
|1 day ago||N||N||N||N||NE|
|2 days ago||N||NW||N||N|
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GEOS Local Image of EDIT
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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Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for Greenville-Spartanburg, SC (6,6,7,8)(on/off)  Help
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