Suwannee River to Keaton Beach out 20 NM Marine Forecast
|Rest Of Today...Southeast Winds 15 To 20 Knots. Seas Around 2 Feet With A Dominant Period Of 4 Seconds. Protected Waters Choppy. Showers And Thunderstorms Likely.|
|Tonight...South Winds 15 To 20 Knots, Diminishing To Around 10 Knots After Midnight. Seas Around 2 Feet With A Dominant Period Of 5 Seconds. Protected Waters Choppy. A Chance Of Showers. Areas Of Fog. A Slight Chance Of Thunderstorms After Midnight.|
|Sunday...Southwest Winds 5 To 10 Knots. Seas Around 2 Feet With A Dominant Period Of 5 Seconds. Protected Waters A Light Chop. Showers Likely With A Slight Chance Of Thunderstorms.|
|Sunday Night...West Winds 5 To 10 Knots. Seas Around 2 Feet With A Dominant Period Of 5 Seconds. Protected Waters A Light Chop. A Chance Of Showers With A Slight Chance Of Thunderstorms In The Evening, Then A Slight Chance Of Showers After Midnight.|
|Monday...Northwest Winds 5 To 10 Knots. Seas Around 2 Feet With A Dominant Period Of 5 Seconds. Protected Waters A Light Chop. A Slight Chance Of Showers In The Morning.|
|Monday Night...North Winds 10 To 15 Knots. Seas Around 2 Feet With A Dominant Period Of 5 Seconds. Protected Waters A Moderate Chop.|
|Tuesday...North Winds 5 To 10 Knots, Becoming Northwest In The Afternoon. Seas 1 To 2 Feet With A Dominant Period Of 5 Seconds. Protected Waters A Light Chop.|
|Tuesday Night...Northwest Winds 5 To 10 Knots, Increasing To 10 To 15 Knots After Midnight. Waves 1 Foot Or Less, Then Around 2 Feet With A Dominant Period Of 5 Seconds After Midnight. Protected Waters A Moderate Chop.|
|Wednesday...Northwest Winds 10 To 15 Knots. Seas Around 2 Feet With A Dominant Period Of 3 Seconds. Protected Waters A Moderate Chop.|
|Wednesday Night...North Winds 10 To 15 Knots. Seas Around 2 Feet With A Dominant Period Of 4 Seconds. Protected Waters A Moderate Chop. Winds And Waves Higher In And Near Thunderstorms.|
| Area Forecast Discussion|
National Weather Service Tallahassee FL
1101am EST Sat Dec 2 2023
Issued at 1048am EST Sat Dec 2 2023
A warm front was analyzed at 15z over the gulf waters, with the entire region entrenched in southeast surface flow. Radar est'd rainfall over the past 6-hours shows a swath of 3-5 inches from Bay County northeastward into Leon County w/ground truth reports around 4 inches. Heavy rainfall will continue to be the greatest hazard today. WPC now has much of the tri-state region in a SLGT risk for excessive rainfall. Given recent trends, the Flood Watch was expanded northeast earlier this morning to include much of the I-10 corridor in the FL Big Bend into the southern tier of GA counties. Severe weather also remains possible today, although convection thus far has been elevated over land areas. Surface based instability will struggle to develop today. But if storms can become sfc-based, they would be able to tap high Bulk Shear and low-level SRH, with an isolated damaging wind and tornado threat, mainly in the FL counties.
Otherwise, Probability of Precipitation was refreshed and temps were lowered a bit.
(Today and tonight) Issued at 308am EST Sat Dec 2 2023
Throughout theNear Term - Rest Of Today Through Tonight
main story will be excessive rainfall, but severe weather will possibly make an appearance across our western areas. Currently, our inland areas are fairly stable, the 00Z upper-air sounding indicated the presence of a couple modest, inversions, generally under 850mb. Although these are expected to erode away provided enhanced WAA (Warm Air Advection - the movement of warm air) later this morning, it explains why we haven't seen much rain accumulation over our inland areas overnight. With cloud bases above 5000 feet, there just isn't enough forcing to bring moist surface air aloft into downpour- producing clouds. This may be starting to change however, we're now seeing higher reflectivities crossing the coastal interface, deeper inland across our FL counties. Still stratiform in nature, this increase in rainfall intensity may help lower cloud ceilings, while closing the gap at the low levels between temps and dew points.
With a synoptic pattern that favors widespread excessive rain; a ridge to the SE and a trough to the NW, today will be characterized as a conveyor belt of showers and storms as they move generally from WSW to ENE. Although lapse rates won't be impressive due to a moist atmospheric column; PWATs (Precipitable Waters) around or greater than 2 inches, forcing for ascent will be provided at the synoptic scale. A messy MCS (Mesoscale Convective System, a complex of thunderstorms which becomes organized on a scale larger than the individual thunderstorms) to our west is associated with a ripple in the 500mb flow, the PV associated with this will move through the region this morning. Later this afternoon, a shortwave quickly moving across the central plains on its way NE will further enhance PV across the region. Thus, combining high moisture content with continuous synoptic forcing for ascent along a SW to NE corridor for hours on end via training showers/convection will lead to flooding concerns. The concern is greatest along the FL Panhandle and SE Alabama where the moisture axis is closest to the source (the Gulf). A flood watch is currently in effect for these areas.
As far as severe weather goes, MLCAPE this afternoon looks to struggle to make it beyond our FL counties. With peak values around 1500 J/kg across the FL Panhandle attention then turns to the LLJ/shear for any signs of organized convection. Current guidance has and LLJ across the area with winds generally around 40-50 kts, which is decent. Now combine these two and we get a sig tor parameter across our FL counties in the range of 1 to 3 this afternoon. Thus, tornadoes are possible, they'll almost definitely be rain-wrapped, making them hard to see. This is not to say tornadoes won't be possible across SE Alabama and SW Georgia, but the parameters don't currently look lined up well enough across these areas.
As we move beyond the afternoon hours and into the evening and overnight hours the main frontal passage is nearing. Southerly flow will further enhance, possibly leading to instability that penetrates deeper into the region. Guidance is currently uncertain on a convective mode, as either semi-discrete or cluster are possible. The LLJ will still be present and if the environment isn't worked over from the afternoon activity, the potential for overnight tornadoes this there. This time however, the threat possibly pushing beyond the FL state line into SE Alabama and SW Georgia.
With multiple hazards possible, whether it's flash flooding, ravine flooding, or tornadoes, make sure to have multiple ways to receive warnings through tonight.
Expect daytime highs generally in the low to mid 70s with overnight lows in the mid to upper 60s.
.SHORT TERM... (Sunday through Monday night) Issued at 308am EST Sat Dec 2 2023
The upper level disturbance and cold front will make its way through the region throughout Sunday. Precip chances are expected to dwindle throughout the day, with perhaps a few rumbles of thunder. Dry weather expected by the later afternoon or early evening, which will continue into Monday. Sunday will be our last unseasonably warm day, with highs in the 70s. Monday's highs will be start of a gradual decreasing trend, with temperatures peaking in the mid to upper 60s for SE AL and SW GA and in the upper 60s to low 70s for FL.
(Tuesday through Friday) Issued at 308am EST Sat Dec 2 2023
Ensemble guidance and cluster analysis shows the SE more or less remaining under weak upper level troughing to near zonal flow through much of the period. The exception could be late in the week where we could experience weak upper level ridging. Nonetheless, the forecast is expected to be dry during this period. A dry cold front is expected to pass through midweek, with surface high pressure forecast before and after that. Temperatures during this period will gradually decrease going from above to near normal, to around or just below normal for this time of year. To put values to that highs will transition from the low to mid 60s to the mid 50s and low 60s, coolest in our AL and GA counties. For overnight lows, expect values to go from spread across the 40s to spread across the 30s by Wednesday night, and then begin to rebound into the mid to upper 30s Thursday night.
Issued at 1048am EST Sat Dec 2 2023
A Small Craft Advisory is now in effect through this afternoon, as elevated winds hold due a disturbance over the region. Outside of this morning, showers and thunderstorm chances will continue through the weekend, some of which may produce gusty winds and waterspouts. The storm system and associated cold front is slated to swing through Sunday night into Monday, turning winds to the northwest to north much of next week. Additionally, a bit of sea fog is possible in Apalachee Bay later Saturday afternoon into Saturday night.
Issued at 308am EST Sat Dec 2 2023
Soaking rains through Sunday morning will keep fire weather concerns at a minimum, which are low dispersions across SE AL and SW GA today and perhaps tomorrow for areas along the coast. A flood watch is currently in effect through Sunday evening across the FL Panhandle and SE Alabama where excessive rainfall is a concern. The cold front is expected to be through the region Sunday night into Monday, cooler and drier conditions move into the region to begin the work week.
Issued at 308am EST Sat Dec 2 2023
No changes were made to the Flash Food Watch that was hoisted yesterday for our AL counties, the western FL Panhandle, and Gadsden, Liberty, and Gulf counties of the Big Bend. Current rainfall amounts vary across the region with areas along and west of the Flint and Apalachicola Rivers seeing the most rain. 24 hour values across SE AL range from 0.15-1.0 inches and for the western FL Panhandle they vary wildly from 0.10-2.2 inches. Elsewhere values range from trace amounts to 0.50, highest near the coast and along the aforementioned rivers.
Rainfall accumulation should mostly occur today with rain chances tapering off Sunday. Forecast rain amounts for this period vary from 2.0-3.5 inches of rain across southeast AL and the western FL Panhandle, 0.75-2.25 inches for the FL Big Bend, and up in southwest GA about 1-2.25 inches. Locally higher amounts will be possible. Storm totals, including yesterday, for areas outside of the flood watch will range from 1 to 3 inches while areas inside the watch should be closer to 3 to 6 inches.
NOAA Tallahassee FL Office: Watches - Warnings - Advisories
FL...Flood Watch through Sunday evening for FLZ007>019-026-027-108- 112-114.
High Rip Current Risk through late Sunday night for FLZ108-112- 114-115.
GA...Flood Watch through Sunday evening for GAZ155>160.
AL...Flood Watch through Sunday afternoon for ALZ065>069.
GM...Small Craft Advisory until 4pm EST /3pm CST/ this afternoon for GMZ750-752-755-770-772-775.