The 12z KTAE sounding is very dry with a PWAT of 0.96", which is about half of normal. The profile also shows mostly light and variable winds through a deep layer as you would expect with stacked high pressure. A few showers have developed offshore from the land breeze but we don`t expect any convection over land areas today.
Highs will be above normal in the mid to upper 90s away from the
Near Term [Through Today]...
We will continue to be under the influence of a very dry air mass and a weakening surface high pressure ridge today, which will lead to another dry and mostly sunny forecast. Projected PWATs and 925mb mixing ratios at 18Z today are around the 1st percentile for this time of year, or about 2.5-3.0 standard deviations below normal.
This degree of dry air should yield surface dewpoints in the 50s, except near the coast. Despite widespread highs in the mid-90s expected today, the unusually low dewpoints should make it feel much less humid than is typical of late August. Lows tonight will be slightly warmer than this morning, but mid-upper 60s are still likely in many areas, particularly north of Interstate-10.
Short Term [Tonight Through Saturday]...
Deep layer moisture will be advected northward on Friday in advance of a shortwave moving into the Mississippi Valley.
The PoP will have a north to south gradient with the highest PoPs (~60%) near the coast tapering down to just 20% across the northern counties. Both the NAM and GFS show PWAT values rising above 2 inches across the area on Friday and Saturday, so some localized heavy rainfall rates and amounts are possible, but the available forcing is not currently expected to be enough to produce widespread heavy rain.
High temperatures are expected to be in the mid 90s, and with an increase in dewpoints, heat indices are expected to reach the 100-105 range across the southern portions of the area on Friday afternoon and across most of the area by Saturday afternoon.
Long Term [Saturday Night Through Thursday]...
The shortwave over the Midwest will gradually dampen out as it lifts across the Great Lakes region. This along with additional shortwave energy translating eastward from the western states will effectively set up nearly zonal flow across most of the CONUS by early next week.
At the surface, the east to west ridge axis will extend across or just north of our CWA with moist onshore flow continuing.
With a return of deep layer moisture along with daytime heating and added instability, look for near to above seasonal PoPs each day.
Despite the increase in rain chances, max temps will generally be above climo in the lower to mid 90s.
Limited cloud cover is expected with VFR conditions expected to prevail. Some brief MVFR VIS is possible with fog at VLD closer to sunrise.
Light to occasionally moderate onshore winds and seas 3 feet or less are expected to prevail through Labor Day.
A very dry air mass across the region and the recent development of drought conditions over parts of the area may contribute to an increased fire danger today.
However, durations of low RH and wind speeds are expected to be too limited to create red flag conditions.
Durations of RH below 28% in Leon County are expected to be around 2-3 hours, which is not sufficient for a Red Flag Warning. However, ERC values are projected to be above 40, so Leon County could be close to observing red flag conditions.
Greater moisture will return by Friday with higher RH values.
A significant increase in deep layer moisture is expected for Friday into Saturday with scattered convection. Some locally heavy rainfall rates and amounts are possible, but widespread heavy rain does not look likely at this time.
Preliminary Point Temps/PoPs...
Tallahassee 97 70 95 74 94 / 0 0 50 40 50
Panama City 91 75 90 77 90 / 10 10 60 40 60
Dothan 95 68 94 73 94 / 0 0 30 30 60
Albany 96 67 96 73 95 / 0 0 20 20 60
Valdosta 94 67 94 72 95 / 10 0 40 30 50
Cross City 94 70 93 73 94 / 10 10 50 40 50
Apalachicola 90 75 89 77 90 / 10 10 60 40 50