textproduct: Jacksonville

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

- Flood Watch for locations west of I-75. Rainfall amounts of 1 to 3 inches, with locally higher amounts of 4 to 6

- Numerous TStorms this Weekend through Early Next Week. Strong Storm Potential Each Afternoon and Evening. Daily Rounds of Heavy Downpours May Cause Localized Flooding

- Moderate Rip Current Risk at Area Beaches on Sunday

UPDATE

The airmass has been worked over pretty good by this evening now with isolated showers or patchy rain over inland areas, which is likely to continue through late evening. There is likely to be some redevelopment of showers after midnight, and then perhaps a few tstorms toward the early morning hours mainly over inland northeast FL. With this in mind, have made a few adjustments to the rain chances rest of tonight but otherwise no other changes anticipated.

NEAR TERM /UNTIL 6 AM SUNDAY MORNING/

Main Highlights through Tonight:

- Rounds of Showers and Thunderstorms, Isolated Strong Storms through the rest of Today

- Locally Heavy rainfall and flooding Possible, mainly west of the I- 75 corridor

Waves of showers and storms will persist through the rest of the afternoon as southwesterly flow will continue to bring tropical moisture into the area, with PWATs sitting in the 2"+ range. Current rainfall totals west of I-75 range between 1 and 3 inches, with the highest totals found in our far western locations of NE FL. With further development of showers and storms expected, could see reasonable higher totals of 4 to 6 inches for some locations. This area remains highlighted with a Slight (level 2 of 4) Risk for Excessive Rainfall from WPC through the rest of Today and into Sunday, with Flood Watch currently in place through the Weekend. Activity will lessen by the overnight hours, but will still have some locations with some showers persisting into Sunday.

The showers across the area is keeping most locations below 90F early this afternoon, with only locations along the SE GA coast in the lower 90s at this time. Overnight lows remain in the 70s. . Highs will be slightly lower than yesterday in the upper 80s along the I-75 corridor to the low 90s elsewhere. Overnight lows remain in the 70s.

SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/

Main Highlights This Period:

- Rounds of Showers and Thunderstorms, Isolated Strong to Severe Storms Possible

- Locally Heavy rainfall potential into Monday

A Flood Watch remains in effect through Monday evening for Gilchrist, Suwannee, southwestern Columbia, western Alachua, and western Marion Counties. Persistent southwesterly flow will transport anomalously deep tropical moisture into the region, with precipitable water values surging to 2.2 to 2.4 inches, nearing daily record levels.

On Sunday, a mid level trough over the southern Appalachians will elongate as Atlantic ridging builds westward. This pattern slows the frontal boundary northwest of the area and strengthens southwesterly flow. Abundant moisture, instability, and large scale ascent will support widespread showers and thunderstorms, initially across inland northeast Florida, expanding northward into southeast Georgia and eastward toward the I-95 corridor.

Widespread rainfall totals of 1 to 3 inches are expected west of I 75 through Monday, with localized amounts of 4 to 6 inches possible in areas of slow moving or training thunderstorms. Flooding remains a primary concern for low lying areas, urban centers, poor drainage locations, and small creeks. The Weather Prediction Center has maintained a Slight Risk (Level 2 of 4) for excessive rainfall across the Suwannee Valley and Flood Watch area, with a Marginal Risk (Level 1 of 4) for the remainder of northeast Florida and southeast Georgia through Sunday.

Isolated strong to severe thunderstorms are possible Sunday and Monday, primarily producing damaging wind gusts of 40 to 60 mph, along with torrential rainfall and frequent lightning. Southwesterly winds will remain breezy at 10 to 15 mph, with gusts up to 20 to 25 mph. Monday, the upper trough evolves into a closed low, maintaining deep moisture and storm coverage through the evening. Temperatures will remain below normal, with highs in the mid to upper 80s inland and near 90 along the coast.

LONG TERM /TUESDAY THROUGH SATURDAY/

Main Highlights This Period:

- Decreasing Coverage of Thunderstorms by Midweek - Heat advisories likely needed Wednesday through Friday

The synoptic pattern will gradually shift mid week as the upper level low lifts northeast and Atlantic ridging expands across the Florida Peninsula. This transition will weaken the prevailing southwesterly flow, returning the region to a typical summertime sea breeze regime.

Scattered to numerous thunderstorms are expected Tuesday as Gulf and Atlantic sea breezes merge near the US 17 corridor. From Wednesday through Thursday, the Atlantic surface ridge axis lifts into southeast Georgia, establishing southeasterly flow. This will push the Atlantic sea breeze inland, triggering collisions with the Gulf sea breeze between Highway 301 and I-75. By Friday, easterly flow will focus thunderstorm development well inland near the I-75 corridor, reducing rain chances at the coast.

Temperatures will trend upward, reaching lower to middle 90s inland from Wednesday through Friday. Heat indices will climb back to 105 to 110 degrees across inland northeast Florida as rainfall and cloud coverage decrease.

AVIATION /00Z SUNDAY THROUGH 00Z MONDAY/

A challenging TAF forecast near and beyond 6 hours from now. Currently, VFR clouds with very little shower/tstorms activity, with most of the light rains west of a line from Waycross to Lake City at 00z. Expect increasing chances of showers and potential isolated storms late tonight into Sunday morning. Periods of MVFR SHRA/TSRA possible late tonight mainly around the GNV area, but even some MVFR cigs all terminals well before any precip arrives, which will be coming from the west or southwest. Anticipate more scattered to numerous showers and a few storms by mid morning and then becoming numerous for the aftn with mostly MVFR conditions prevailing. In addition, we have TEMPO and PROB30 groups for the showers and storms. Generally, looks like better IFR TSRA chances at GNV for Sunday.

MARINE

A prevailing offshore wind flow is expected through early next week. High coverage of mainly afternoon and evening thunderstorms are expected Sunday through Tuesday. A few strong storms will be possible each afternoon and evening through Tuesday. A weak cool front over Georgia will shift slowly southeast on Sunday and Monday. This will help strengthen southwest winds beginning Sunday morning, with Caution level wind speeds likely, and periods of Small Craft Advisory conditions, especially over northern waters through early Monday.

Rip Currents: Prevailing offshore winds this weekend through Monday will likely yield a low to low-end moderate risk at area beaches.

FIRE WEATHER

Main Highlights This Period:

- Isolated strong to severe thunderstorms through Monday. - Locally heavy rainfall. - Gusty and erratic winds near convection. - Heat advisories likely needed Wednesday through Friday

An active, wet pattern persists through the weekend as a nearly stationary frontal boundary lingers near southeast Georgia. Persistent southwesterly flow will drive numerous to widespread showers and thunderstorms through Monday.

Outside of storms, southwesterly winds of 10 to 15 mph (gusts 20 25 mph) are expected across northeast Florida. Fire weather operations should anticipate sudden, erratic wind shifts associated with thunderstorm outflows. Dispersion values will generally remain good due to increased transport winds, though cloud cover and precipitation will limit daytime mixing heights.

Fog Potential: Significant fog development is not expected during the next several mornings. Isolated strong to severe thunderstorms are possible into the weekend with gusty winds up to 40-60 mph in thunderstorms. In addition, outflows from distant thunderstorms may also produce gusty and erratic winds.

PRELIMINARY POINT TEMPS/POPS

AMG 73 88 73 88 / 40 90 70 80 SSI 76 90 77 89 / 50 70 50 90 JAX 73 88 73 89 / 40 80 60 80 SGJ 74 88 74 89 / 30 70 30 60 GNV 72 85 72 87 / 60 80 70 80 OCF 73 86 73 88 / 50 80 50 60

JAX WATCHES/WARNINGS/ADVISORIES

FL...Flood Watch through Monday evening for FLZ021-035-236-340-522. GA...None. MARINE...Small Craft Advisory from 2 PM Sunday to 8 AM EDT Monday for AMZ450-452-470-472.