textproduct: Charleston

SYNOPSIS

High pressure will prevail across the region most of this week, bringing dry conditions and above normal temperatures. A cold front may bring showers and colder temperatures to our area next weekend.

NEAR TERM /THROUGH TONIGHT/

Today: Aloft, broad ridging just to the west will gradually flatten leaving mostly west-northwest flow across the forecast area. At the surface, high pressure will start the day across New England to the VA Tidewater then shift offshore through the afternoon. An inverted surface trough just off of our coast will remain offshore and gradually lose definition. This setup will leave the forecast area within a weakly forced regime, with light northeast flow in the morning turning more southerly and weak into the afternoon as the high shifts offshore. Early morning mid and high level clouds will pass offshore, leaving behind an area of stratus likely situated across the western half of the area. This stratus will mix and lift through mid to late morning, leaving some diurnal cumulus for the afternoon. The forecast is dry, though there will likely be some shower activity within the aforementioned offshore trough. However, hi- res model guidance is unanimous that any shower activity that develops will remain offshore. Today will begin the ramp up in high temperatures that will continue through the week. Highs are forecast to peak in the upper 60s just about everywhere, with a few locations tipping into the low 70s.

Tonight: Dry and mostly quiet condition will prevail across the forecast area. Temperatures will be much milder, with lows forecast to only fall into the mid 40s inland ranging to the low 50s along the coast. Model guidance suggests that at least patchy fog will occur across the inland tier, with potential for even greater coverage than that.

SHORT TERM /TUESDAY THROUGH THURSDAY/

As a surface low tracks across the Great Lakes region, high pressure will build over the northeastern Gulf and allow for rather quiet conditions to continue. Expect temperatures to be a bit warmer than Monday with highs in the low to mid 70s on Tuesday, and mid to upper 70s on Wednesday and Thursday! It'll be cooler at the beaches as the SST should keep the temperatures in the the mid to upper 60s. Forecast notes it'll be a bit breezy on Tuesday evening into Wednesday as the pressure gradient tightens up. A rain-free forecast has been maintained through the period as subsidence associated with the high will keep the atmosphere quiet. Overnight lows remain very mild for January with the majority of the region staying above 50s.

LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/

Ensembles continue to note that an upper-lvl trough situated over the central CONUS will approach the region on Friday and take hold of the forecast over the weekend. Temperatures on Friday still look to reach into the mid to upper 70s even with this pattern change and there's a chance that we could see some record breaking temps. at KSAV and KCHS (see Climate Section). Also, along with this upper-trough, an associated cold front will try to pass through the region this weekend. There's some differences on how this event will unfold as some guidance has been indicating that the front will wash out before it arrives, and others have it making it all the way to the coastline. However, as of right now, the highest chance of precipitation looks to be Saturday evening out ahead of the front. Behind this system, expect a bit of a cool down compared to the previous week as temperatures stay in the upper 50s to low 60s early next week.

AVIATION /06Z MONDAY THROUGH FRIDAY/

The 06z TAF period begins with VFR conditions in place at KCHS, KJZI, and KSAV. Observations and web cams show that there are patches of shallow fog around, producing very short-lived visibility reductions in the 2-4 mile range. However, mid and high level clouds are thickening aloft which should help to prevent fog from becoming too widespread. Through sunrise, the main concern is actually for very low stratus currently across south GA to spread northward and into KSAV closer to sunrise. We have introduced a TEMPO group to address this possibility. KCHS and KJZI could see brief periods of shallow fog, but should be prevailing VFR. No concerns for the daytime hours on Monday. There could be another round of fog and stratus concerns Monday night, though the best chances will be beyond the end of the 06z TAF period.

Extended Aviation Outlook: VFR through Thursday. An approaching cold front could bring increased probabilities for flight restrictions later Friday.

MARINE

Today through tonight: The morning will feature northeast winds up to around 10 knots across the local waters. The gradient will then steadily weaken through the afternoon, with speeds dropping off to around 5 knots. Overnight, the flow will actually turn more westerly with time with speeds remaining quite low around 5 knots. Seas will average 2-3 feet through most of the period, perhaps up to 4 feet at times in the outer GA waters.

Tuesday through Friday: South-southwesterly winds at 10 to 15 kts with gusts up to 20 kts will prevail on Tuesday afternoon through Wednesday morning as the pressure gradient tightens up. Thereafter, expect winds to veer more westerly at 5 to 10 kts on Wednesday afternoon into Thursday, before switching to south- southeasterly on Thursday afternoon into Friday. Ahead of the approaching system, winds become a bit breezy on Friday, however conditions stay under Small Craft Advisory criteria. Not much of a swell to talk about, seas range 2 to 3 ft through the period. Forecast notes PoPs across the Atlantic through the period, thus some light showers could be possible (esp. overnight).

CLIMATE

Record High Temperatures: January 9: KCHS: 78/2012 KSAV: 77/2008

Record High Minimum Temperatures: January 9: KCHS: 58/1946

CHS WATCHES/WARNINGS/ADVISORIES

GA...None. SC...None. MARINE...None.