We're entering the typically busiest part of the hurricane season, so it's no surprise to see the tropics coming to life. The National Hurricane Center (NHC) is watching four areas in the Atlantic for possible tropical cyclone development.
This morning's 7-day outlook from NHC shows a quartet of areas of interest in the Atlantic Basin.
The one closest to home doesn't look all that interesting on satellite imagery. It's a tropical wave along 73° west, and there is only a small blob of thunderstorm clouds near the wave's northern end, affecting the southern Bahamas and Turks and Caicos islands. This wave is tracking west and won't have any impact on us. But once it reaches the 90° waters over the Gulf of Mexico, the thunderstorms should become more intense and widespread. Given enough time, a low-pressure area should form, and this could quickly turn into a tropical cyclone as it moves over that hot water. It's final destination is likely to be Texas. NHC says this feature has a 30 percent chance for development next week.
A loop of true color visible satellite imagery from midday today, showing the four features of interest in the Atlantic Basin.
To the east, another tropical wave is along 53° west over the tropical Atlantic, just east of the Lesser Antilles. It's hard to pick out because it's hidden in the Intertropical Convergence Zone, but there is a broad turning motion here, and some models show this feature developing in a few days as it moves through the eastern Caribbean Sea. This one has the best chance of the four to directly affect South Carolina, so I'm watching it closely. Some of the models indicate it develops, then it tracks across Hispaniola, then wanders east of The Bahamas for a while around next weekend.
The next feature is one we've been watching for days, another tropical wave along 44° west in the tropical Atlantic. There appears to be a coherent area of low pressure along this wave centered near 14° north and 44° west, so this one has a chance to become a tropical cyclone soon. There are two possibilities for this feature. One is that it joins forces with the wave to its west and is a part of a storm east of The Bahamas later next week. The other school of thought keeps this feature separate, tracking northward far to our east over the Atlantic next week. NHC gives this wave a 40 percent chance to develop over the next seven days.
And finally, the most robust feature in the Atlantic right now is a tropical wave along 33° west, to the west of Cabo Verde. There is a large-scale turning with this feature and widespread associated thunderstorms, so this one has the best chance to develop quickly. However, computer models agree that this feature will remain far to our east and move northward into the middle of the Atlantic. NHC gives this feature a 70 percent chance to develop over the next week.
A fresh cloud of Saharan dust is emerging from Africa now; that signals a brief break in the African tropical wave train. But, more waves are lined up over Africa to emerge into the Atlantic next week.
Finally, we had a cold front that moved through the Southeast earlier this week, and this front has become stationary over the northern Gulf of Mexico and off the East Coast. We always watch these features for a sneaky development close to home.
Now is the time to prepare for hurricanes if you have been slacking on stocking your hurricane kits! The busiest part of the hurricane season is underway and will last another seven weeks. If you need preparation advice, visit hurricane.sc for tips.
A chart from NOAA showing the climatology of tropical cyclone activity in the Atlantic Basin with August 18 highlighted.
Once again, a cold front, perhaps better described as a 'not as hot front', pushed farther south than usual and through South Carolina to give us a break from the usual summertime heat and humidity. A second reinforcing front moved through last night, and there has been a substantial drop in humidity behind this front.
This sets us up for a relatively nice weekend. Most of the state will remain rain-free; only the Lowcountry will see just a stray afternoon shower or thunderstorm because of the dry air over the state. Don't expect any miracles with temperatures; highs will still reach the lower 90s over most of the state but the low humidity will make it very tolerable and about as pleasant as we can reasonably expect it to be in mid-August. Don't forget sunscreen if you'll be out in the sun for extended periods.
One downside is that those wildfires are still going up in Canada and Canada is the source of the air mass that is moving into our part of the world, so we might see some haze from the wildfire smoke at times. However, it won't be thick, cough and sneeze-inducing smoke like we have seen at times in recent months.
The party ends on Monday as we get thrown into the oven again. Temperatures trend up on Monday, though humidity remains relatively low, and that helps keep the middle-to-upper 90s somewhat bearable. The dry air in place keeps our usual afternoon thunderstorms at bay.
Bearable may not be a word to describe Tuesday. While humidity will remain lower than usual, temperatures will shoot up to the upper 90s with the I-20 hot spots reaching 100 or so. We'll see few afternoon thunderstorms, if any, again on Tuesday.
After that, the forecast becomes uncertain. We can say confidently that a cold front will push in from the north or northeast in 'backdoor' fashion on Wednesday, though the timing is uncertain. The later it arrives, the more likely we remain in the oven on Wednesday with highs in the 95-100 range, but there's a good chance the front arrives early enough that we get relief from the heat as the wind shifts to the northeast. With the front comes the chance for thunderstorms, which might be severe if the front's timing is such that temperatures shoot up toward 100 again before storms start firing up.
Forecast questions abound at the end of next week. Will the breath of fresh air from the northeast hang on for a few days, or will the oven-like heat in the nation's midsection expand back into South Carolina quickly? Will the old front be able to cause more thunderstorms Thursday into Friday or will it fizzle fast? Will my new kitten ever allow me to have eight hours of uninterrupted sleep again? The answer to the latter is probably around this time next year but the answer to the first two questions is uncertain and you'll want to check in with your friendly neighborhood TV meteorologist or the National Weather Service for updates.
While we're not sure how long the respite from the heat will last, it does appear to be only temporary; next weekend is looking rather hot again.
