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

- Scattered to Numerous Afternoon & Evening Thunderstorms Each Day through the Weekend and Early Next Week. Primary concern will be heavy downpours resulting in localized flooding. Strong thunderstorm risk will shift inland toward the U.S. Highway 301 and I-75

- Moderate Rip Current Risk Continues at All Area Beaches

NEAR TERM /THROUGH TONIGHT/

Highlights Today and Tonight:

- Heavy rainfall/localized flooding remains the main threat from thunderstorm activity today, mainly between the I-95 and US-301 highway corridors

Today will be a transition as steering flow from the Southwest this morning to the south of stalled frontal boundary across SE GA will shift slowly to the Southeast later this afternoon and tonight as high pressure builds north of the region and the stalled frontal boundary slowly washes out over the weekend. Expect current light to moderate rainfall across inland SE GA to end during the early morning hours, the expect some low stratus and patchy fog over inland areas towards sunrise. Partly sunny skies develop this morning with an East coast sea breeze development by the late morning hours which will push slowly inland during the transition to the SE steering flow through the afternoon hours. Max Temps remain below normal across inland SE GA near the old frontal boundary with highs in the mid/upper 80s, while most of NE FL should reach into the lower 90s with peak heat indices of 100-105F this afternoon. The main threat from storms along the slowly inland East Coast sea breeze will be heavy rainfall/localized flooding, mainly from the I- 95 corridor inland to the US-301 corridor, as PWATs still remain on the high side near or slightly above 2 inches through the day, with heavy rainfall threat across both NE FL and SE GA, mainly from 3pm- 9pm time frame. This activity will continue to shift slowly inland through the late afternoon/evening hours towards the I-75 corridor, where some interaction with the Gulf Coast sea breeze could continue the heavy rainfall threat. A few strong storms can still be expected with gusty winds to 40-50 mph and frequent lightning and cannot rule out an isolated severe storm with downburst winds of 60 mph across inland NE FL where some more intense heating occurs this afternoon. Evening convection over far inland areas will fade after sunset, then as low level flow becomes more onshore/SE during the overnight hours, expect focus to shift to the Atlantic Coastal waters where scattered showers and isolated storms will be possible, along with a few showers making it all the way to the Atlantic beaches towards morning. Low temps in the lower/middle 70s inland, and upper 70s along the Atlantic Coast. Some patchy fog and low stratus will be possible over inland areas towards morning as well.

SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/

Main Highlights This Period: (Sunday through Monday night)

- A few strong storms possible each afternoon, with gusty winds and heavy rainfall

An upper high will build over head this period. At the surface high pressure will be centered to the northeast. With the surface high to the northeast, the low level flow will be from the east. This will push the east coast sea breeze well inland each afternoon. Convection this period, will be driven by diurnal heating, and aided by the sea breeze as it passes through. While the ridge aloft will increasingly become a limiting factor for the strength of storms through the period, ample moisture will be in place to keep the daily coverage above average.

Temperatures will trend near to little above average this period.

LONG TERM /TUESDAY THROUGH FRIDAY/

Main Highlights This Period: (Tuesday through Friday)

- A few strong storms possible each afternoon, with gusty winds and heavy rainfall

Little change in the overall pattern through Wednesday, with surface high pressure centered to the northeast, with high pressure aloft. The flow around the surface high will continue to yield an onshore flow with east coast sea breeze pushing well inland.

The surface high will build more toward the east later in the week, as a trough develops along the east coast of the US. The upper high will remain in place through the end of the week. The change in position of the high later in the week, will lead to more of a flow from the southeast vs east.

In general, scattered afternoon and evening convection is expected. While a few strong storms can not be ruled out, the chance will be lower this week due to the high aloft. Heavy rainfall in storms will likely be the main hazard this period.

A gradual increase in daily temperatures is expected this period, with readings mostly running above average.

AVIATION /12Z SATURDAY THROUGH 12Z SUNDAY/

Early morning obscurations and low ceilings are expected to be cleared out by around 14z midmorning with showers and eventual thunderstorms developing throughout the day and into tonight. Vicinity and on-site thunderstorms will develop by around 17z to 19z, initially for coastal sites and Duval County sites and then pressing inland towards GNV until around 03z to 05z. Potential for MVFR and IFR visibilities early Sunday morning for VQQ and GNV, starting by around 06z.

MARINE

A shift to onshore winds this weekend as high pressure builds to the north of the local waters and remains in place through much of next week. This will lead to decreasing chances for showers and storms over the weekend and into next week as onshore flow develops.

Rip Currents: A more solid Moderate risk of rip currents will develop this weekend in the onshore flow as surf/breakers slowly increase to 2 to 3 feet. This pattern will continue into early next week as well.

FIRE WEATHER

Surface high pressure will build to the northeast Today, and remain centered there through the middle of next week. The high will build more toward the east later in the week. Prevailing onshore winds from the Atlantic this are expected this week, with the east coast sea breeze pushing well inland each day. Thunderstorms are forecast each afternoon, but the chances will decrease after Monday.

Fog Potential: Significant fog is unlikely during the next several days. Gusty and erratic winds can be expected in and near thunderstorms.

PRELIMINARY POINT TEMPS/POPS

AMG 86 72 91 72 / 40 30 50 10 SSI 85 77 87 77 / 40 30 30 20 JAX 90 74 88 74 / 60 20 40 10 SGJ 88 75 87 76 / 40 30 40 10 GNV 91 73 90 73 / 80 40 70 10 OCF 92 73 91 73 / 60 40 60 20

JAX WATCHES/WARNINGS/ADVISORIES

FL...None. GA...None. MARINE...None.