Area Forecast Discussion

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

- Extreme to Exceptional Drought Continues. Dry Conditions Will Support Increase Risk of Fire Spread

- Red Flag Inland SE GA Today, Fire Weather Watch Monday for most of the inland areas. Breezy Winds and Critically Low Minimum Humidity this afternoon and Monday

- Gusty Coastal & Hazardous Boating Conditions Tonight. Small Craft Advisory in effect beginning this evening. Moderate to High Risk of Rip Currents Monday

NEAR TERM /THROUGH TONIGHT/

- Dry conditions will support Critical and Elevated Fire Concerns

A cold front currently stretching across coastal SE GA into Suwannee Valley will continue to move southeastward across the area today as a mid/upper level trough sweeps across the SE states. A few showers developing along and behind the front could bring very light rain or sprinkles to SE GA and the I-10 corridor this afternoon. Moisture will be very limited and there likely won't be any measurable accumulations from these showers. Breezy northwesterly winds develop in the wake of the front and spread across the area bringing sustained 10-15 mph winds with gusts around 25 mph this afternoon. Drier air filters in lowering Min RHs to critical levels in inland SE GA. The combination of breezy winds, critical humidity, and exceptional drought for this afternoon prompted the issuance of Red Flag warnings for Atkinson, Coffee, and Jeff Davis counties. Cloudy skies and moisture from the front will limit more widespread critical fire concerns from developing. Breezy conditions will remain along the coast during the evening and overnight hours as winds begin to shift to northeasterly. Overnight lows will be in the mid 50s to lower 60s across NE FL, while SE GA will be cooler in the upper 40s to low 50s.

SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/

Main Highlights This Period:

- Fire Weather Watch along and south of I-10 over inland NE FL on Monday - Critically low minimum humidity values inland each day - A period of elevated onshore flow Monday

On Monday, the broad base of a mid-upper level trough will exit the area with rising heights as ridging builds in through early Tuesday. In it's wake and behind the cold front from today, strong high pressure builds in from the northwest and north keeping the pressure gradient tight against the departing front. This will produce breezy northeast flow for much of the area but especially near the coastal areas from Fernandina Beach southward.

Dry air from the sfc to aloft will help lower dewpoints for Monday into the 20s and 30s where we have a fire weather concerns. This combined with the gusty winds will create dangerous fire weather conditions, mainly for inland southeast GA and northeast FL.

The temperatures on Monday will be near to slightly below normal in the mid 70s coast to about 80 degrees inland. Monday night sees mostly clear skies. This will help lead to decent radiation cooling given that winds should quickly drop off as a piece of the high pressure system gets centered over portions of the area. Lows are forecast all the way down to 45-50 degrees inland and mid 50s at the coast.

On Tuesday, increased ridging aloft will help rebuild high pressure to the north of the area. Onshore flow and stable conditions will lead to a pleasant day with highs a bit closer to normal. Still, given the severe drought and some occasional breezy winds, fire weather concerns remain high. Tuesday night, not as cool with lows in the 50-60 deg range with some airmass moderation from the onshore flow and perhaps a few more high clouds moving in ahead of a mid level trough over the central Gulf coast.

LONG TERM /WEDNESDAY THROUGH SUNDAY/

Main Highlights This Period:

-Dry conditions persist into next week into Friday -Isolated T'storms possible Saturday and Sunday -Warming Trend this Period

Shortwave trough will bring a period of some high clouds over the region Wednesday through Thursday morning while surface high pressure ridge will settle into the area with fairly weak sfc flow except for a breezy afternoon sea breeze at the coast. Some increase in low level moisture expected due to the east-southeast low level flow. Thursday onward, the ridge of high pressure at the sfc and aloft looses some of its strength with the sfc high pushing further offshore to the east and southeast. This will result in further warm up but still largely dry conditions. PWATs do rise a bit from 0.70 inches on Wednesday to about 1.2 inches by Saturday and Sunday, which is at or slightly above the norm for this time of year. By Saturday into Sunday, a weak cool front will move into the eastern U.S., but remains to the north and northwest of our area. There may be enough moisture to kick off a few showers or thunderstorms on Saturday (forecast POPs of 20-30 percent), mainly forced from the west and east coast sea breezes. Dewpoints at least rise to upper 50s and lower 60s bringing in some better sfc moisture. However, confidence in this latter POP forecast is a bit uncertain given the relatively dry conditions persisting.

Temperatures will begin with highs near normal Wednesday and above normal Thursday into Sunday. Low temperatures will be near normal through Friday and slightly above normal on Saturday and Sunday.

AVIATION /18Z SUNDAY THROUGH 18Z MONDAY/

VFR conditions will persist through TAF period. Breezy northwesterly around 10-15 kts continue this afternoon as a cold front moves through the area. Gusts will occasionally be in the 20-25 kt range. Winds shift to north-northeasterly after 00Z, with gusty winds continuing along the coastal sites.

MARINE

A cold front will move through the waters during the afternoon hours today. The front will bring a rapid wind shift to the north this afternoon and evening, then a surge of northeast winds following the frontal passage through Monday night. Small Craft Advisories are in place from tonight and into Monday Night. Winds and waves subside Monday night as high pressure builds into the area for mid-week.

Rip Currents and Surf:

A low to moderate risk of rip currents Today due to offshore west to northwest flow ahead of a cold front. High/moderate risk of rips expected early this week as a strong NE wind surge develops behind the cold frontal passage.

FIRE WEATHER

- Red flag warning until 8 pm EDT this evening for portions of southeast Georgia

- Fire weather watch from Monday afternoon through Monday evening for portions of northeast and northern Florida

- Fire weather watch from Monday morning through Monday evening for portions of southeast GA

- Critically low minRH values today over inland southeast Georgia and much of inland northeast Florida

- Areas to widespread high daytime dispersion rest of today through Thursday.

A cold front is moving through the area today which will result in northwest winds becoming 10-15 mph gusting to 20-25 mph, but clouds and moisture ahead of the front will prevent MinRH values from falling to critical levels, limiting the risk for Red Flag conditions except for Atkinson, Coffee, and Jeff Davis counties where a Red Flag Warning remains in effect.

On Monday, strong high pressure will build in from the northwest with breezy northeast winds near 15 mph gusting to 25 mph and critical MinRH values 15-20 percent will create dangerous wildfire conditions and a Fire Weather Watch is in effect for all of inland Southeast GA in addition to Northeast FL locations along and just south of the Interstate 10 corridor. The breezy surface and transport winds will create high dispersions Monday.

High pressure will be over the area Tuesday and Wednesday before gradually moving east of the area Thursday into Friday, with dry conditions persisting and critical MinRH values over inland Southeast GA and portions of northeast FL each day this week. Breezy east to northeast winds Tuesday will diminish Wednesday with daily Atlantic seabreeze moving well inland into Friday. Areas to widespread high daytime dispersions are expected daily into at least Thursday due to high mixing heights and moderate transport wind speeds.

FOG POTENTIAL AND OTHER REMARKS: There will be potential for Localized "superfog" near the vicinity of any smoke from ongoing wildfires

CLIMATE

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

April 19: JAX 92/1995, CRG 91/2013, GNV 94/2011, AMG 91/1968

PRELIMINARY POINT TEMPS/POPS

JAX WATCHES / WARNINGS / ADVISORIES

FL...Fire Weather Watch from Monday afternoon through Monday evening for FLZ021-023-024-030-031-035-120-136-220-232- 236-322-422-425-522. High Risk for Rip Currents from Monday morning through late Monday night for FLZ124-125-138-233-333. GA...Red Flag Warning until 8 PM EDT this evening for GAZ132-133- 149. Fire Weather Watch from Monday morning through Monday evening for GAZ132>136-149-151>153-162-163-165-250-264-350-364. MARINE...Small Craft Advisory from 8 PM this evening to 11 AM EDT Monday for AMZ450. Small Craft Advisory from 8 PM this evening to 8 PM EDT Monday for AMZ452-470-472. Small Craft Advisory from 11 PM this evening to 10 PM EDT Monday for AMZ454. Small Craft Advisory from 11 PM this evening to 2 AM EDT Tuesday for AMZ474.