Charleston Weather

Tropical Depression 3/Bonnie very unlikely to impact Charleston

Jared Smith — Thu, 22 Jul 2010 13:22:58 +0000

It’s likely we’ll see Tropical Depression 3 or Bonnie classified at 11am, according to the National Hurricane Center. It’s highly unlikely that Bonnie would pose a threat to the Charleston area (see the NWS Charleston forecast discussion for more). The computer models are in great agreement that TD-3/Bonnie will head near or over extreme South Florida before curving into the Gulf of Mexico (where a second landfall is less clear). South Carolina and Georgia are stuck under a ridge of high pressure which is keeping things quite hot — heat advisories will be around for several more days, it looks like — and redirecting storm systems around it. According to the NWS forecast discussion, the most TD-3/Bonnie may do is train in some drier air which may inhibit afternoon thunderstorms later this week.

I’ll continue to keep watch to the tropics; we’re heading into August and are just a few weeks from the climatological peak of hurricane season, so don’t let this slow start fool you — there’s plenty of time for more storms.

Record temperatures — of the low kind

Jared Smith — Sun, 04 Jul 2010 15:02:45 +0000

This morning, North Charleston set a new record low with a low of 61. The previous record, 63, was set back in 1947(!!). This should make for one of the most pleasant Fourths of July in recent memory in the Charleston area. Enjoy it while it lasts; the Bermuda high, which is our typical summertime pattern, kicks back in by Tuesday and will start to warm things up again. I hope you have a safe and enjoyable holiday!

The severe weather threat so far has yet…

Jared Smith — Mon, 03 May 2010 23:18:48 +0000

The severe weather threat so far has yet to really materialize. Some strong storms flared earlier in the day, bringing some persistent heavy rain (at times dumping near a half-inch per hour according to radar estimations) across Colleton County into portions of Dorchester County. The storms have been on a weakening trend, though, as the expected instability has not yet yielded any major weather. RADAR indicates some storms packing heavy rain in Georgia, gradually moving NE, but the tornado threat has thankfully not borne itself out. As the sun goes down, so goes the threat for severe thunderstorms. After sunset, we’ll turn our attention to a swath of persistent heavy rain that has slowly been making its way across the Midlands. It will arrive overnight and stick with us through a lot of Tuesday. Thankfully, it’s been dry, which would mitigate any severe flooding, though we can’t rule out troubles downtown tomorrow morning.

Tornado Watch until 10 PM for inland counties

Jared Smith — Mon, 03 May 2010 19:25:22 +0000

The inland counties are under a tornado watch until 10 PM as a cold front advances against the seabreeze, creating a shear environment favorable for isolated tornado development in addition to large hail and damaging winds. But don’t take my word for it, here’s NWS in the latest Area Forecast Discussion:

ALREADY SEEING SEVERAL CLUSTERS OF STRONG TO SEVERE TSTMS
DEVELOPING ALONG THE LEDGE EDGE OF THE RAIN SHIELD IN CENTRAL
GEORGIA AS THEY ENCOUNTER THE WESTERN FRINGES OF THE INSTABILITY
AXIS THAT IS IN PLACE ACROSS EASTERN SOUTH CAROLINA INTO SOUTHEAST
GEORGIA. SEVERAL OF THESE CELLS HAVE ALREADY EXHIBITED SUPERCELLULAR
CHARACTERISTICS WITH OCCASIONAL MODEST GATE-TO-GATE SHEAR ZONES
NOTED. ATTM IT APPEARS THE RISK FOR SEVERE WEATHER WILL BE
GREATEST ALONG AND WEST OF A MONCKS CORNER-EARLY BRANCH-
STATESBORO-REIDSVILLE LINE. THE RISK MAY EXTEND FARTHER EAST TO
THE CHARLESTON AND SAVANNAH METRO AREAS DEPENDING ON HOW MESOSCALE
PROCESSES ALIGN LATER THIS EVENING…BUT THE INCOMING MARINE LAYER
IN THE WAKE OF THE SEA BREEZE SHOULD HELP SUPPRESS STRONG
CONVECTIVE UPDRAFTS FROM FORMING. WILL CONTINUE TO HIGHLIGHT LARGE
HAIL AND DAMAGING WINDS IN THE GRIDS AND TEXT PRODUCTS THIS
EVENING AWAY FROM THE COAST. WILL ALSO MENTION RAIN MAY BE HEAVY
AT TIMES AS INCREASING PWATS AND THE POTENTIAL FOR CONVECTIVE
TRAINING COULD LEAD TO SOME LOCALIZED FLOODING PROBLEMS.
FINALLY…THERE WILL ALSO BE A POTENTIAL FOR ISOLATED
TORNADOES…MAINLY WHERE MESOSCALE BOUNDARY INTERACTIONS SUCH AS
THE SEA BREEZE LOCALLY ENHANCE 0-1KM HELICITY VALUES.

It’s worth noting that the coastal counties are not under a watch right now — that being said, there is always the possibility of a severe thunderstorm near (but not officially within) the watch area, so everyone in the Charleston metro area should keep an eye out this afternoon. Watch @chswx for any warnings or additional watches throughout the day.

Sunday severe threat

Jared Smith — Sun, 25 Apr 2010 13:17:11 +0000

The storm system that’s put the Midwest, Alabama, Mississippi, Tennessee, and Kentucky under the severe weather gun over the past two days is pushing toward the coast today. While the atmospheric ingredients are certainly nowhere near what is needed for the widespread tornadic activity to our west, the potential remains for damaging winds, large hail, and perhaps isolated tornadoes over the Lowcountry.

Storms with occasionally heavy rain are trekking across the area this morning. Those will move aside by midday, allowing for a bit of clearing and heating to occur, which could fuel additional thunderstorm activity through this evening. High tide at Charleston Harbor is at 6:48 PM, so any heavy thunderstorms along the coast this evening might also cause some flooding trouble downtown.

Here’s what the Storm Prediction Center has to say:

…CAROLINAS…
AMPLE LOW LEVEL MOISTURE HAS RETURNED TO PARTS OF SC/NC TODAY WITH
DEWPOINTS IN THE MID 60S. WATER VAPOR LOOPS SUGGEST RAPID MID LEVEL
DRYING WILL OVERSPREAD THIS REGION TODAY…BRINGING STRONG HEATING
AND VEERING LOW LEVEL WINDS. SEVERAL MODEL SOLUTIONS SUGGEST THE
POTENTIAL FOR ISOLATED THUNDERSTORM DEVELOPMENT LATE THIS AFTERNOON
OVER EASTERN SC/NC…WITH STORMS TRACKING NORTHEASTWARD TOWARD THE
COAST AFTER DARK. IF THIS SCENARIO OCCURS…THERE WOULD BE A RISK
OF HAIL AND DAMAGING WINDS IN THE STRONGEST CELLS.

And from NWS Charleston:

SEVERE THUNDERSTORMS…A STRONG STORM SYSTEM WITH A HISTORY OF
PRODUCING SEVERE WEATHER ACROSS THE SOUTHEASTERN UNITED STATES…
WILL CONTINUE TO MOVE EASTWARD TODAY. THE RISK OF SEVERE WEATHER
IS EXPECTED TO SHIFT INTO SOUTHEAST GEORGIA AND THE EASTERN
CAROLINAS TODAY AHEAD OF A COLD FRONT. WHILE ISOLATED
THUNDERSTORMS WITH LARGE HAIL AND DAMAGING WIND GUSTS ARE POSSIBLE
THROUGH LATE MORNING…THE BETTER CHANCES FOR SEVERE WEATHER WILL
BE FROM AROUND MIDDAY INTO THIS EVENING ACROSS THE REGION. IN
ADDITION TO LARGE HAIL OF 1 INCH OR GREATER AND DAMAGING WIND
GUSTS…THERE IS A POTENTIAL FOR ISOLATED TORNADOES.

Follow @chswx on Twitter and you can receive watches, warnings, and other periodic forecasts to your cell phone simply by using Twitter’s built in SMS service. Watch @chswxextra for updates to this blog or additional background information as events unfold.

Of course, the most reliable source of weather information and warnings is a NOAA Weather Radio. You can pick these up at most grocery stores, RadioShack, etc. Ensure that your alarm is set to the “on” position so you can be immediately alerted to any severe thunderstorm or tornado warnings that may be issued.

Quiet for the next several days

Jared Smith — Thu, 01 Apr 2010 05:26:44 +0000

Expect a nice, quiet several days ahead (including the weekend). We’ll be getting a touch of May here in the first couple days of April with temperatures hitting the mid-80s inland with few clouds in the sky, making for a fantastic early beach weekend. We’ll have a cold front come through on Sunday to moderate things a bit, but not seeing much in the way of a precipitation chance from it so far. Otherwise, the only real nuisance is the pollen — pollen counts are extremely high right now, making your cars yellow and a lot of you not feel great. With this nice weather hanging around, don’t expect to get much relief.

More later on this week. Enjoy it, Charleston!

Welcome to Spring: Slight risk of severe weather today

Jared Smith — Sun, 28 Mar 2010 18:19:11 +0000

The Storm Prediction Center has the area in a slight risk for severe weather this afternoon. Dewpoints are headed well into the 60s across the area, and we’ve gotten more sunshine than first anticipated today, which will aid convection throughout the area. Current timing shows that the bulk of the activity is expected around and after midnight; an overnight severe threat currently cannot be ruled out and must be watched closely.

I’m currently seeing some isolated moderate showers move quickly northward over Moncks Corner, Lake Moultrie, and surrounding areas. A line of storms has kicked up in Georgia and is about to cross 95 into southern SC (Colleton, Beaufort, and Jasper counties). There’s also a cluster of thunderstorms moving eastward that might bring some rain/thunder to Summerville and North Charleston if it keeps it together.

Look for increasing winds tonight as high pressure is forced out by the cold front causing all this fun. A strong onshore flow is expected which may push tides near the 7′ mark, which is the threshold for shallow coastal flooding in beach communities and downtown Charleston.

Running conversation about today’s potential for rough storms is happening on Twitter at @chswxextra. Watch for any severe weather watches and warnings, as well as periodic conditions updates, on @chswx on Twitter and @chswx on Identi.ca.

Introducing @chswxextra

Jared Smith — Tue, 23 Feb 2010 06:12:07 +0000

In an effort to keep the signal-to-noise ratio on @chswx high, I’ve decided to open a new Twitter account called @chswxextra. @chswxextra is intended as an enhancement to the alerts broadcast on @chswx.

Why another account? I am constantly thinking about how to make and keep @chswx as useful as possible. Sometimes, less is more — and I find that’s absolutely the case when it comes to @chswx. You shouldn’t hear from it (outside of the periodic forecasts) unless conditions are taking a turn for the worse. I also believe that @chswx should be as accessible of a follow as possible, whether you’re on TweetDeck or receiving SMS tweets on a phone with no data plan. Of course, this is quite limiting, too — in a rapidly-developing situation, I’d often link off to the NWS or this blog with an expanded explanation of what’s going on.

So, to best serve the widest range of users, I’ve decided to create @chswxextra, which as I described before is an enhancement to the alerts given on @chswx. @chswxextra is inspired by an idea at TheDigitel Charleston: @thedigitelextra, which gives additional commentary on a developing news situation to those who want more than just the regular Digitel Twitter feed. @chswxextra is much in that same vein. It provides the backchannel conversation to an ongoing event, complete with links to blog posts, NWS statements, multimedia, and more. It is not an account you follow over SMS; rather, it’s something you follow when you want more than just the alerts or the forecast — and I know there are plenty of you out there.

So, check out @chswxextra and be sure to let me know what you think!

Winter weather event well underway

Jared Smith — Fri, 12 Feb 2010 23:27:52 +0000

Winter weather reports overlaid on RADAR from 6:15PM.

No doubt about it — the forecast has verified and the Charleston area is well-encompassed in a winter weather event. Reports of snow are coming in from all over the place, primarily from inland locations (particularly in Berkeley County and Summerville). Accumulations of 1″ have been observed in Goose Creek. Snow will continue to push toward the coast — as I write this, there are fresh reports of snow in Shadowmoss in West Ashley — making for quite a fun winter weather Friday for the Lowcountry.

I strongly discourage travel this evening, as snow will make visibilities very low at times. Also, there was quite a bit of rain that fell today ahead of this event, and there’s a good chance that could refreeze and create very slick spots on the roadways. This is also a concern for Saturday.

Hopefully I’ll have snow pictures of my own soon!

Winter Storm Warning begins at noon

Jared Smith — Fri, 12 Feb 2010 14:19:11 +0000

snOMG! Charleston is looking at its first appreciable snowfall in over ten years this evening as a low pressure system develops and moves northeast, paralleling the coast and drawing in the necessary cold air to create what could be a potentially significant snow event (significant, at least, for our area — this will be no DC blizzard). NWS is forecasting up to 6″ inland — up from the 4″ expected yesterday. It’s very likely the wintry precipitation will reach the coast, so we do expect to see at least a rain/snow mix downtown. Confidence is very high in the forecast, as the forecast models have excellent agreement for a snow event across most of the state.

While we don’t expect this event to snow people in, it is anticipated that travel will be hairy starting this afternoon through tomorrow. NWS released a safety statement a little while ago with some winter weather safety tips.

We’ll be watching as the storm approaches throughout the day. Tag your photos and posts with #chswx and they’ll show up in the Collecta widget in the sidebar.