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

- Moderate to High Risk for Rip Currents at All Area Beaches Today.

- Patchy Fog Possible at Inland Locations Early on Wednesday Morning.

- Isolated to Widely Scattered Thunderstorms Wednesday through Thursday

- Scattered Thunderstorms and Widespread Beneficial Rainfall Possible During the Weekend. Potential Rainfall Totals of 1-3 Inches Wednesday through Sunday.

NEAR TERM /THROUGH TONIGHT/

Main Highlights This Period:

- Moderate to High Risk of Rip Currents at Area Beaches.

- Patchy Fog Possible at Inland Locations Early on Wednesday Morning.

High pressure across the eastern seaboard gradually weakens as it shifts southward off the coast of the southeastern seaboard by tonight. Patchy fog will be possible early this morning across inland SE GA and Suwannee Valley where winds decouple and skies clear. The fog combined with any smoke near wildfires will create localized superfog conditions, greatly lowering visibility. Dry airmass (PWATS 0.5-0.8 in) and building subsidence will keep the area rain-free today. Winds subside and shift to easterly with the high building to our east and the developing afternoon Atlantic sea breeze. Highs today warm into the upper 70s along the coast to the upper 80s-90 further inland. An upper shortwave will move through the SE US later tonight potentially bringing a few showers to the Ocmulgee river basin. Patchy fog will be possible early Wednesday morning for inland NE FL where skies will be clearer. With flow shifting to SE, lows tonight will be in the low-mid 60s.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/

Main Highlights This Period:

- Suppressed ridging southward will allow for disturbances to move to the region and eventually bring unsettled weather to the area

- Rain chances are enhanced for north portions Wed-Wed night, and then all of the area Thurs-Thurs night. An isolated strong storm or two is possible.

On Wednesday, a shortwave disturbance will be passing across the area early in the day that will be bringing a chance of convection to the northern zones, with a cool frontal boundary moving through the eastern U.S. Pre-frontal troughing is apparent in the guidance across our area with a prevailing southwest flow by the afternoon that will be breezy at times. Very warm temps in the 80s to lower 90s expected reaching near record highs.

Wednesday night, yet another mid level disturbance will be over the central Gulf coast Wednesday evening, heading eastward, and into our area after midnight. The frontal boundary will be headed to our area and should be at the Altamaha River Basin by about 6 AM Thursday. Scattered convection is anticipated, with model soundings showing elevated instability to support t-storms as well. A severe threat looks low at this time, but not out of the question as there may be some chance of wind threat with some of the storms. Above normal lows in the 60s expected given the warm regime ahead of the front.

Thursday, the frontal boundary and possible frontal wave energy will sag southeastward across the area prompting rain chances over much of the area for the day. Main precip area initially will be across southeast GA, and then during late morning and through the aftn focused over northeast FL. At this time, severe threat looks like owing to weak instability. Max temps will be limited from cloud cover and the cool front and therefore so lower max temps than Wednesday. The front does look to slow, if not begin to stall late in the day into Thursday night. Both the NAM, GFS, and ECMWF show this nearly stationary front across northeast FL or north central FL on Thursday night, which should continue to support a chance of precip into the night, though not high chances.

Overall, this midweek period marks the beginning of a transition toward a more unsettled pattern.

LONG TERM /FRIDAY THROUGH MONDAY/

Main Highlights This Period:

- Unsettled weather but beneficial rains expected.

- Isolated strong/severe storms possible Saturday.

As we head into Friday, the stationary frontal boundary will be draped across portions of northeast FL first half of the day, and then may begin to lift northward in response to sfc frontal wave development west of the area along the north Gulf coast. There is a chance of showers and possibly a couple of t-storms as the daytime heating and the frontal boundary will serve as a focus for lift. In addition, a localized weak wave of low pressure along the front may transit eastward across far southeast GA. Frontal forcing and lift may increase as we move into Friday night with the approach of stronger frontal wave, with low level flow increasing from the southwest. Expect a chance of showers and possible thunderstorms from about I-10 corridor northward.

GFS and ECMWF show the warm front lifted up into southeast GA early Saturday with the formed sfc low that was along the Gulf coast approaching our area. The GFS shows more of a potential severe weather threat than the ECMWF, with the GFS showing greater instability ahead of the renewed cold front trailing a sfc low that's over central GA. The threat would be damaging winds and perhaps a tornado threat, though confidence remains low. In any event, elevated rain chances are anticipated Saturday into Saturday night as the cold front pushes through the forecast area and then to near north central FL by near sunrise on Sunday.

For rest of Sunday, the front will be moving southeastward over the FL peninsula, but overrunning clouds and precip are anticipated for the morning hours (especially northeast FL) with possible lowering of rain chances during the afternoon and certainly by the evening as energy moves east of the area. However, there are model differences in how long this overrunning period lingers and so confidence at this point drops further.

Model consensus indicates late Sunday night the front and associated low shifting east and southeast of the area. This will lead to decreasing rain chances into early Monday. Thus, expect Monday will be dry behind the front and high pressure will build in from the north producing a north to northeast flow.

Temperatures will be near or above normal Friday. Still quite warm/above normal Saturday over northeast FL ahead of the cold front and below normal for southeast GA. Cooler conditions expected Sunday and Monday, with temperatures trending slightly below normal.

AVIATION /12Z TUESDAY THROUGH 12Z WEDNESDAY/

IFR ceilings at JAX and CRG, accompanied by a few light showers or sprinkles early this morning, are expected to improve to MVFR by 13Z and VFR by 14Z. MVFR ceilings at SGJ and VQQ are expected to improve to VFR towards 15Z. VFR conditions at GNV and SSI may briefly deteriorate to MVFR towards 13Z, but conditions should improve to VFR towards 15Z. IFR conditions are then expected to develop towards 08Z at VQQ as high cloud cover that moves overhead later this afternoon begins to thin out during the predawn hours on Wednesday. Surface winds will become northeasterly around 5 knots before 14Z, followed by winds shifting to east-northeasterly at 5-10 knots by 17Z at the inland terminals, while speeds at the SGJ and SSI coastal terminals increase to 10-15 knots by 18Z. Surface winds will shift to southerly while gradually diminishing to around 5 knots by 02Z this evening.

MARINE

Weakening high pressure will shift southward off the southeastern seaboard today. A cold front will then enter the southeastern states on Wednesday, possibly bringing a few showers and thunderstorms to the Georgia waters Wednesday night. This front will then move south across the rest of our local waters on Thursday and Thursday evening, accompanied by showers and thunderstorms. A wave of low pressure develops over the Gulf this weekend, likely spreading additional showers and thunderstorms across our local waters during the upcoming weekend.

Rip Currents:

High risk of rip currents is expected across NE FL beaches today due to onshore winds and long period swells. High end moderate risk prevails at SE GA beaches.

FIRE WEATHER

- High Daytime Dispersion Likely Wednesday

- Patchy High Daytime Dispersion Thursday

Dry today as northeast morning winds turn more east- southeasterly in the afternoon. Min RH will be as low as the mid 30s west of U.S. Highway 301. On Wednesday, a breezy southwest flow develops and lower RH values are expected down as low as 30-35 percent.

High dispersion values are expected on Wednesday ahead of the next frontal boundary where mixing heights during the afternoon range from 6.0 to 7.5 kft with s prevailing west- southwesterly transport winds at 15 to 20 mph. Patchy high dispersion possible on Thursday with west to slightly northwest transport winds at 15 mph.

Chances of wetting rains increases from around the I-10 northward on late Wednesday night into Thursday, including the potential for isolated thunderstorms. There's also the potential for more rain for the weekend.

FOG POTENTIAL AND OTHER REMARKS: Patchy fog is possible inland early on Wednesday morning. Smoke from nearby fires may result in localized visibility reductions, especially during the overnight and early morning hours.

CLIMATE

Record High Temperatures at NE FL/SE GA climate sites:

April 29: KJAX: 93/1991 KGNV: 95/2017 KAMG: 93/2012 KCRG: 91/2021

PRELIMINARY POINT TEMPS/POPS

AMG 86 64 89 65 / 0 20 20 40 SSI 78 66 86 68 / 10 0 10 30 JAX 83 63 92 66 / 10 0 10 20 SGJ 81 64 89 67 / 0 0 10 10 GNV 89 61 92 65 / 0 0 10 10 OCF 89 63 90 66 / 0 0 10 0

JAX WATCHES/WARNINGS/ADVISORIES

FL...High Risk for Rip Currents through this evening for FLZ124-125-138- 233-333. GA...None. MARINE...Small Craft Advisory until 9 AM EDT this morning for AMZ472- 474.