341 
FXUS62 KJAX 251803
AFDJAX

Area Forecast Discussion
National Weather Service Jacksonville FL
203 PM EDT Thu Sep 25 2025

...New NEAR TERM, SHORT TERM, LONG TERM, AVIATION, MARINE, FIRE 
WEATHER...

.KEY MESSAGES...

For the latest NE FL and SE GA Daily Key Messages please visit:
https://www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf

- Thunderstorm Coverage Increases through Saturday.

- Weekend Tropical Development Expected Near the Bahamas. Increasing
  Marine & Surf Zone Hazards Early & Middle Portions of Next Week

- Moderate Rip Current Risk Continues at Area Beaches

&&

.NEAR TERM...
(through Tonight)
Issued at 202 PM EDT Thu Sep 25 2025

Afternoon and evening showers and storms will build over the forecast
area today with the areas most likely for convective development 
occurring along the sea breeze boundaries and along areas of 
collision. Southwesterly winds will build in over inland areas 
today and allowing the west coast sea breeze further eastward with
the vicinity of the sea breeze merger expected to occur between 
the Highway 301 and I-95 corridors by late afternoon and into the 
early evening hours. High temperatures today will rise into the 
lower 90s this afternoon with overnight low temperatures dropping 
into the lower 70s.

&&

.SHORT TERM...
(Friday through Saturday night)
Issued at 202 PM EDT Thu Sep 25 2025

Troughing aloft will continue to dig into the southeastern states
on Friday, with a shortwave trough currently located at the base 
of this feature near the Ozarks / Tennessee Valley expected to 
slow its forward progress as it traverses the southeastern 
states. This trough and its associated shortwave will drive a 
frontal boundary into our area by late Saturday. Deepening 
southwesterly flow will transport tropical moisture into our 
region ahead of this approaching front on Friday, with PWATs 
rising above 2 inches across most of our area before sunset. 
Energy embedded within this strengthening southwesterly flow will 
develop numerous thunderstorms over the FL panhandle and the 
northeastern Gulf on Friday morning, with this activity 
progressing eastward towards the I-75 corridor and inland 
southeast GA during the early to mid afternoon hours. Cloud cover 
will thicken from west to east on Friday, with morning sunshine 
east of the I-75 corridor in FL and along/east of U.S.-301 in 
southeast GA allowing temperatures to soar into the lower 90s, 
with maximum heat index values rising to the 100-105 degree range 
for these locations. The Atlantic sea breeze will develop and push
inland towards the I-95 corridor by the early to mid afternoon 
hours, setting up colliding mesoscale boundaries for areas east of
I-75 during the afternoon, with activity progressing quickly 
northeastward towards coastal locations towards sunset. Although 
bulk southwesterly shear values will only be around 20-25 knots, 
colliding mesoscale boundaries may result in pulsing storms, 
particularly around the I-95 corridor. Stronger storms tomorrow 
may be capable of producing downburst winds of 35-45 mph along 
with frequent lightning strikes. Faster storm motion tomorrow 
should negate the risk for flooding rainfall, especially given 
antecedent dry soil conditions across our area.

Additional rounds of convection are likely across our area on
Friday night and Saturday as deep southwesterly flow prevails 
downstream of troughing digging into the southeastern states and 
the approaching frontal boundary. Extensive cloud cover should 
limit instability during this time frame, limiting chances for 
stronger storms. However, locally heavy downpours are possible, 
with these downpours being largely beneficial unless they 
repeatedly move across or "train" over urban or low-lying areas. 
Lows on Friday night will fall to the upper 60s and lower 70s, 
with highs on Saturday remaining in the 80s. The frontal boundary 
should then push eastward across our region on Saturday afternoon 
and evening, with lingering evening convection possible along the 
I-95 corridor. Inland lows should fall to the mid and upper 60s 
for southeast GA and the Suwannee Valley, with lower 70s 
prevailing at coastal locations.

&&

.LONG TERM...
(Sunday through next Thursday)
Issued at 202 PM EDT Thu Sep 25 2025

A complex weather pattern will exist late this weekend and early  
next as a tropical disturbance currently near Hispaniola moves 
northwestward across the Bahamas this weekend, likely developing 
into a tropical depression or a tropical storm (Imelda). 
Meanwhile, troughing over the Deep South will cutoff as a ridge 
takes shape over the Upper Midwest and the Mississippi Valley, 
with Atlantic ridging remaining in place over Bermuda. This ridge 
will likely steer strengthening Tropical Cyclone Humberto between 
Bermuda and Cape Hatteras by Tuesday. Humberto will likely be a 
major hurricane over the western Atlantic, and it could interact 
somewhat with Invest 94L (Imelda) early in the week. However, 
Invest 94L will likely move on a north-northwest to northwesterly 
course towards the southeastern seaboard, primarily being steered 
by the cutoff upper trough over the Deep South. 

This developing tropical cyclone and a gradually building surface
ridge over the Ohio Valley and Great Lakes will tighten our local
pressure gradient beginning on Sunday, with the aforementioned 
frontal boundary expected to stall just off the Atlantic coast,
trailing southwestward across central FL. Northeasterly winds will
become breezy at coastal locations by Sunday afternoon, with 
showers expected to increase in coverage and frequency by Sunday 
evening along the I-95 corridor. Meanwhile, a drier air mass will
filter into southeast GA and the Suwannee Valley, where mostly 
sunny skies and dewpoints falling through the 60s will boost highs
to the upper 80s to around 90. Highs at coastal locations should 
remain mostly in the mid 80s. Lows Sunday night will fall to the 
mid to upper 60s for inland southeast GA and the Suwannee Valley
and the lower 70s elsewhere. 

A low confidence forecast currently exists for early next week,
all predicated on the future movement and intensity of Invest 94L 
(Imelda). Peripheral wind and rainfall impacts are expected along
the I-95 corridor, but any deviation westward in the future oath
of this system will bring increasing impacts to a larger portion
of our area. We expect northerly winds to become breezy on Monday
if this potential tropical cyclone remains offshore, with
northwesterly winds then developing on Tuesday if this system
pivots inland across the southeastern states. Highs will likely
remain in the 80s during the early to middle portions of next 
week.

&&

.AVIATION...
(18Z TAFS)
Issued at 202 PM EDT Thu Sep 25 2025

Showers and storms will continue to develop through the afternoon
and into the early evening hours, reaching the vicinity of the 
Jax Metro sites by around 20z. Convection will disperse by around 
02z-04z with winds becoming more mild and variable overnight for 
inland sites. Potential for patchy fog developments affecting GNV 
and VQQ during the early morning hours on Friday between around 
06z-10z. 

&&

.MARINE...
Issued at 202 PM EDT Thu Sep 25 2025

High pressure shifts south of the area today as a front approaches 
from the northwest. Southerly flow increases ahead of the front 
today and Friday with increasing thunderstorm chances. The front 
moves south of the local waters Saturday. Northeast winds increase 
Sunday and Monday as high pressure strengthens north of the region 
and a potential tropical system nears the Bahamas. Building seas and
increasing winds nearing Advisory levels are expected early next 
week as the tropical systems tracks north of the Bahamas. Local 
interests should monitor the latest forecasts on this potential 
tropical cyclone from the National Hurricane Center.

&&

.FIRE WEATHER...
Issued at 202 PM EDT Thu Sep 25 2025

Southwesterly surface and transport winds will weaken on Friday and 
Saturday as a frontal boundary slowly traverses our region. 
Widespread showers and thunderstorms are expected across our area. 
Elevated mixing heights on Friday will persist across portions of 
northeast and north central Florida, where good daytime dispersion 
values are forecast. Fair to poor values are expected elsewhere due 
to increasing cloud cover and rainfall chances, and fair to poor 
values are then expected area-wide on Saturday. Surface and 
transport winds will then shift to northeasterly on Sunday. 

&&

.CLIMATE...
Issued at 159 AM EDT Thu Sep 25 2025

Yesterday,9/24, Gainesville tied the record high of 95 
(previously set in 1925). All other climate sites were within 1 
degree of the record high for the date. 

High temperatures will once again near daily record highs today: 

DATE     9/25     Normals 

JAX      96/2019  High: 86 
CRG      95/2019  High: 85 
GNV      96/1931  High: 87  
AMG      98/1961  High: 86 

&&

.PRELIMINARY POINT TEMPS/POPS...
AMG  70  87  68  84 /  40  80  70  50 
SSI  73  87  72  83 /  20  70  70  60 
JAX  72  92  71  86 /  20  80  50  70 
SGJ  73  90  72  86 /  20  60  60  70 
GNV  71  92  70  88 /  10  70  50  70 
OCF  73  90  72  86 /  10  60  40  70 

&&

.JAX WATCHES/WARNINGS/ADVISORIES...
FL...None.
GA...None.
AM...None.
&&

$$