National Weather Service Mobile AL
137pm CDT Fri July 12 2024
Near Term
(Now through Saturday) Issued at 137pm CDT Fri July 12 2024
An upper level ridge stretching southwest over the northern Gulf of Mexico from the open Atlantic is bisected by a shortwave system off the FL/GA/SC/NC coast this morning. This shortwave system is expected to weaken into the weekend, allowing the upper ridge over the Southeast and Gulf to build. A weakly organized surface low has organized off the Atlantic Seaboard, pushing drier air south over the eastern half of the Southeast. Southwesterly flow around a surface ridge stretching west over the Gulf of Mexico is moving Gulf moisture inland over the Lower Mississippi River Valley and western portions of the Southeast, shifting a band of higher moisture levels ( with precipitable h20 values > 2") along the coast inland over Mississippi and southwestern-most Alabama. Also helping to move the moisture inland is a seabreeze forming daily along the Gulf coast and moving inland today and Saturday. This unbalanced approach to the moisture along with the upper ridge building over eastern portions of the Southeast will allow for a better chance of rain further inland the further west one goes in the forecast area. Am expecting areas along and north of Highway 84 to see little to no rain today, with scattered showers and thunderstorms possible closer to the Mississippi and Alabama coast. Rain chances see a greater inland coverage for Saturday as more Gulf moisture works its way inland.
Temperatures remain above seasonal norms as the upper ridge builds, with mid to upper 90s expected today and Saturday. Heat indices in the 100 to 105 degree range today rise into the 102 to 108 degree range Saturday as moisture levels increase. A Heat Advisory will likely be needed Saturday. Temperatures tonight fall into the low to mid 70s inland to upper 70s to near 80 along the coast.
A low risk of Rip currents is expected into the coming week, even as the tidal range increases. Lack of significant swell is the reason. /16
SHORT AND Long Term (Saturday night through Thursday) Issued at 458am CDT Fri July 12 2024
To start the period, an upper level shortwave will be moving east across the Ohio Vally region and off the Mid Atlantic coast by the end of the day on Sunday. Meanwhile, upper level riding will be building over the Southeast and Gulf Coast region by Sunday and will persist across the area through Wednesday. The ridging will deflect most of the weak shortwave energy in the flow aloft to our north from the end of the weekend through Wednesday or next week. By Thursday of next week, a stronger shortwave trough will be approaching our area with the upper ridging breaking down.
Precipitable water values initially in the 1.90 inch range on Sunday increase to the 2.0 to 2.2 inch (possibly even a little higher at times) range for the remainder of the forecast period. This deep layer moisture, combined with daytime heating, sea breeze interactions, and residual outflow boundaries will result in a typical summertime convective pattern of scattered afternoon and early evening showers and thunderstorms Sunday through Wednesday. Daily Probability of Precipitation in the 30 to 50 percent range will prevail. By Thursday, as the upper ridging breaks down with the stronger shortwave approaching and also a surface frontal boundary beginning to make its way south into the Southeastern CONUS, look for a possible slight uptick in chances for showers and storms on Thursday (with a Probability of Precipitation of around 60 percent). The severe weather risk will generally be low through the period, but localized storms could be strong enough to produce brief wind gusts in excess of 40 mph, frequent lightning and locally heavy downpours.
Away from storms, which will provide temporary relief from the summer heat, daytime highs range from the mid to upper 90s. This combined with surface dewpoints well into the 70s suggest heat index values will be on the increase in the extended period, and Heat Advisories may be required. This will be particularly true for our western and coastal sections of the forecast area (where afternoon heat indices could return to the 108 to 112 degree range). Overnight lows will remain rather consistent, ranging from the low to mid 70s over inland areas to the upper 70s along the coast (with barrier islands likely remaining in the lower 80s overnight). DS/12
NOAA Mobile AL Office: Watches - Warnings - Advisories
AL...None. FL...None. MS...None. GM...None.
