Suwannee River to Keaton Beach out 20 NM Marine Forecast
|Rest Of Today...South Winds 15 To 20 Knots. Seas 4 To 6 Feet With Occasional Seas Up To 8 Feet. Dominant Period 6 Seconds. Protected Waters Choppy. Slight Chance Of Thunderstorms In The Morning. Chance Of Showers Through The Day. Chance Of Thunderstorms In The Afternoon.|
|Tonight...Southeast Winds 15 To 20 Knots. Seas 4 To 6 Feet With Occasional Seas Up To 8 Feet. Dominant Period 5 Seconds. Protected Waters Choppy. Chance Of Showers And Slight Chance Of Thunderstorms.|
|Sunday...Southeast Winds 15 Knots. Seas 4 To 6 Feet With Occasional Seas Up To 8 Feet. Dominant Period 7 Seconds. Protected Waters A Moderate Chop. Chance Of Showers And Thunderstorms.|
|Sunday Night...Southeast Winds 10 To 15 Knots. Seas 3 To 5 Feet With Occasional Seas Up To 6 Feet. Dominant Period 8 Seconds. Protected Waters A Light Chop. Chance Of Showers And Thunderstorms.|
|Monday...South Winds 10 To 15 Knots. Seas 3 To 5 Feet With Occasional Seas Up To 6 Feet. Dominant Period 6 Seconds. Protected Waters A Light Chop. Chance Of Showers And Thunderstorms.|
|Monday Night...Southwest Winds 10 Knots Becoming Southeast 10 To 15 Knots In The Late Evening. Seas 2 To 4 Feet. Dominant Period 6 Seconds. Protected Waters A Light Chop. Chance Of Showers And Thunderstorms In The Evening, Then Slight Chance Of Showers And Thunderstorms After Midnight.|
|Tuesday...Southeast Winds 15 Knots. Seas 2 To 4 Feet. Dominant Period 5 Seconds. Protected Waters A Moderate Chop. Chance Of Showers And Thunderstorms In The Morning. Slight Chance Of Showers And Thunderstorms In The Afternoon.|
|Tuesday Night...Southeast Winds 10 To 15 Knots. Seas 2 To 4 Feet. Dominant Period 5 Seconds. Protected Waters A Moderate Chop.|
|Wednesday...Southeast Winds 15 Knots. Seas 2 To 4 Feet. Dominant Period 5 Seconds. Protected Waters A Moderate Chop. Slight Chance Of Showers And Thunderstorms Through The Day.|
| Area Forecast Discussion|
National Weather Service Tallahassee FL
127pm EDT Sat May 21 2022
14am EDT]... Near Term - Through Tonight
An active day is expected with a weak upper trough moving over the area in conjunction with strong instability and some mid-level dry air. This environment will enhance the potential for strong to severe downbursts to develop with convection later today. As an example, the 04z HRRR (High-Resolution Rapid Refresh) forecast sounding at Tallahassee valid at noon today shows SBCAPE values near 4000 j/kg with a fat CAPE profile and DCAPE around 1100 j/kg. The Wet Microburst Severity Index (WMSI) is also forecast to be over 80 today by several members of the SREF, indicating the potential for 50+ knot downbursts. With these factors in mind, the Storm Prediction Center outlook for a marginal risk of severe storms across the area looks good with damaging wind the main threat. Given the fat CAPE profiles, some hail cannot be ruled out as well, although deep layer shear is on the weak side. Steering flow is also on the weak side, which will likely lead to slower moving storms with numerous boundary collisions. Localized pockets of heavy rain can be expected this afternoon with storms, although widespread heavy rain amounts are not expected. Some localized flooding in urban and poor drainage areas is possible if storms move over those areas. High temperatures are expected to range from the mid 80s to low 90s.
Heading into tonight, convection will gradually diminish after sunset over land, and some redevelopment offshore is expected for late tonight. Overnight lows are expected to be mainly around 70 with slightly warmer lows along the immediate coast.
.SHORT TERM [Sunday Through Monday]... Active weather spills over into Sunday as an unseasonably moist airmass remains in place. The axis of precipitation initially shifts westward near an approaching frontal boundary before convective coverage expands areawide during the afternoon hours when instability is greatest. Embedded impulses in the west-to-southwest flow aloft traversing the service area should act to enhance activity. Therefore, more rounds of scattered to numerous showers and storms capable of producing heavy rainfall are expected. Rain chances modestly decrease from east to west on Sunday night before ramping back up on Monday. A lobe of mid-level vorticity tracking across northern AL looks to focus the convection the most from the Panhandle to north of the I-10 corridor on Monday. Outflow boundaries could also lead to secondary cell development.
Given the high instability and weak synoptic flow, several strong and a couple isolated severe storms are likely, with gusty/erratic winds and microbursts being the primary threats. The latter is suggested once again by the WMSI in which several SREF members show decently high potential through the short-term period. Hail up to 1" is also possible in the strongest cells.
Widespread high temperatures in the 80s are forecast through the period, with low 90s favoring the southeast Big Bend/lower I-75 corridor. Locations that experience the greatest rainfall may see temperatures closer to the mid 80s (i.e., southeast AL/western Panhandle). Muggy overnight lows in the upper 60s to low 70s are in store for us.
Long Term - Monday Night Through Saturday
We revert to a more typical summertime pattern in the beginning of the long-term thanks to the front becoming diffuse and a developing subtropical ridge axis nosing towards the FL peninsula. The rainfall forecast consequently reflects isolated to scattered showers and storms (mainly slight chance PoPs).
A longwave trough is still poised move across the central US mid- week, then lift along the Appalachians while dragging an attendant front over the region. The aforementioned ridge weakens in response, which should allow rain chances to increase Wednesday-Thursday. There is better consensus among global models on frontal passage occurring late Friday or early Saturday. Relatively drier air filters in, which should help lower temperatures and dew points by a few degrees by then, particularly in the northwest portions of the service area.
High temperatures are forecast to be mostly in the 80s, with the best chances for low 90s away from the coast on Wednesday. Friday is shaping up to be the "coolest" day of the period when mid-80s are on tap for southeast AL and parts of southwest GA. Lows in the upper 60s to low 70s will continue to be common until the front clears around the start of Memorial Day Weekend (low-mid 60s).
Prevailing cautionary boating conditions are expected much of this weekend from south to southeast winds up to 20 knots with prospects for scattered thunderstorms looking favorable. Brief periods of advisory level winds and seas are possible, especially near any strong storms.
Conditions improve to below headline criteria by Sunday night and persist into mid-week. Thunderstorms look to focus closer to the coast during that timeframe in a more typical summer-afternoon fashion while isolated convection likely develops in the early- morning hours.
A rather active weather pattern is in store for the next few days with scattered to numerous showers and storms possible each day, beginning in the mid-morning and continuing into the afternoon. Gusty winds and frequent lightning will be possible with the stronger thunderstorms.
A tropical airmass will make for wet weather this weekend that may pose an isolated flood threat. Scattered to numerous showers and thunderstorms capable of being efficient rainmakers are forecast during that time. Excessive Rainfall Outlooks by WPC have adjusted from 24 hours ago, which show a Marginal Risk (level 1 of 4) for the east Big Bend and Suwannee Valley - Valid 12Z Saturday to 12Z Sunday. The risk then shifts to generally west of the Apalachicola River from 12Z Sunday to 12Z Monday.
Although storm-total Quantitative Precipitation Forecast through Monday is less than 1", the potential to exceed those amounts for a given area is there. Worst- case 48-hour accumulations from our local CAM guidance suggests 3-6" with up to 3" possible on Saturday or Sunday. These possibilities are contingent on where storms initiate and evolve. Given the antecedent dry conditions across the Tri-state area, many locations should be able to handle the impending precipitation, but minor nuisance flooding is possible, particularly at urban spots, poor- drainage, or low-lying areas. Rivers remain in good shape.
We are looking at a more typical summertime rainfall forecast early next week before wetter conditions return Wednesday-Thursday, followed by a drying trend heading into Memorial Day Weekend.
NOAA Tallahassee FL Office: Watches - Warnings - Advisories
FL...High Rip Current Risk through late Monday night for Coastal Bay- Coastal Franklin-Coastal Gulf-South Walton.
GA...None. AL...None. GM...None.