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. Critically Low Minimum Humidity Values Inland Each Day. Dry Conditions Will Support Increase Risk of Fire Spread

- Fire Weather Watch Monday Afternoon. Set for Inland Southeast Georgia & Portions of Inland Northeast Florida

- Gusty Coastal & Hazardous Boating Conditions Tonight. Small Craft Advisory in effect This evening

NEAR TERM /THROUGH TONIGHT/

- Critically low minimum humidity values inland SE GA - Dry conditions will support Elevated Fire Concerns

A cold front pushes through Today as a mid/upper level trough sweeps across the SE states. Northwesterly winds along and behind the front will range from 15-20 mph with gusts upward of 25-30 mph. Elevated Fire concerns remain as even drier air begins to filter into the area behind the front during the afternoon hours, and through the overnight hours into Monday. A few isolated showers may be possible across coastal SE GA as the front pushes through the area, but chances remain low. A gradient of daytime highs Today as locations in SE GA will range from the mid 70s to mid 80s, while NE FL will range from the lower 80s to lower 90s.

Breezy conditions will remain along the coast during the evening hours as winds begin to shift to be from the NE. Overnight lows will be in the mid 50s to lower 60s across NE FL, while SE GA will be cooler in the upper 40s.

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

Monday, the base of a mid to upper level trough will move offshore of the SE US coast with ridging aloft move into the region in it's wake, which will allow strong high pressure to build in from the NW. A tight pressure gradient between the high and the exiting cold front to the south will create strong onshore NE winds 15-20 mph over much of NE FL gusting to 30 mph along the coast and 25 mph inland. Much drier air will advect into the area bringing very low dewpoints as low as the mid 20s across inland SE GA during the day and into the 30s just inland of the coast which, in turn, will create very low relative humidity values of 15-20 percent across interior SE GA about 20-25 percent along and west of highway 301 over inland NE FL. For these locations, the combination of breezy north to northeast winds and very low humidity will highlight a threat of dangerous wildfire conditions. A Fire Weather Watch has been expanded to include all of inland SE GA beginning 8AM Monday through sunset. Highs on Monday will be below normal along the coast and I-95 with mid to upper 70s, warming to near normal values inland near I-75 into the upper 70s to near 80 degrees.

Monday night, low level ridging just to the NW of the area mostly clear skies will support radiational cooling and below normal lows down into the mid to upper 40s over most of inland SE GA and inland NE FL with low 50s along I-95 and north central FL and values closer to normal in the mid 50s along the coast.

Tuesday, strong ridging aloft will be in place northward into the central appalachians and move onto the Mid Atlantic coast. This will support strong high pressure over MD/VA slowly working to the Delmarva peninsula through the afternoon. Clockwise flow around the synoptic feature will bring ENE breezy onshore flow 10-15 mph gusting to 25 mph from the beaches to I-95 and and 8-15 mph inland gusting to 20 mph. Low level ridging will be over SW GA and the FL panhandle, with dry, subsident air lowering humidity values inland to critical levels, elevating wildfire risk. Highs will be near normal along I-95 in the upper 70s to near 80 degrees and mid 70s at the coast to above normal inland in the low 80s.

LONG TERM /WEDNESDAY THROUGH SATURDAY/

Main Highlights This Period:

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

High pressure will gradually shift east of the area Wednesday into Friday with a cold front approaching on Saturday. Daily seabreeze circulation will bring the Atlantic seabreeze well inland through Friday with breezy east to southeast winds at the coast working inland in the afternoon. Dry conditions will continue with low humidity values over inland NE FL while inland SE GA will have critically low humidity values each afternoon. The low level wind flow will become southerly Friday night and then Southwesterly on Saturday ahead of a front moving in from the NW, keeping the Atlantic seabreeze pinned near I-95. Isolated T'storms will form in the afternoon due to strong heating, increasing moisture and lift from seabreeze interactions as the Gulf seabreeze moves well eastward towards I-95.

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

AVIATION /12Z SUNDAY THROUGH 12Z MONDAY/

VFR conditions will persist through TAF period. Westerly winds this morning quickly shift to northwesterly and increase to around 10 kts by 18Z as a cold front moves through the area. Breezy winds in the afternoon with gusts 15-20 kts. 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 risk of rips and potential high surf advisory conditions expected early next week in strong NE wind surge behind cold frontal passage.

FIRE WEATHER

-Critically low MinRH values Today over inland Southeast Georgia and much of inland Northeast Florida

-Areas of high daytime inland dispersions Today

-Near Critical MinRH values Sunday afternoon over inland Southeast Georgia

-Widespread high daytime dispersions Monday through Friday

A cold front will moving through the area today with light westerly winds after sunrise turning northwesterly and very breezy midday to early afternoon 10-15 mph gusting to 20-25 mph, but clouds and moisture ahead of the front appear will prevent MinRH values from falling to critical levels until late this afternoon before sunset, limiting the risk for Red Flag conditions. Monday, strong high pressure will build in from the northwest with very breezy northeast winds near 15 mph gusting to 25 mph and well below critical MinRH values 15-20 percent will create dangerous wildfire conditions and a Fire Weather Watch has been included 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 each day this week. Breezy east to northeast winds Tuesday will diminish Wednesday with daily Atlantic seabreeze moving well inland into Friday with east southeast onshore flow. High dispersions are expected daily into Friday due to high mixing heights and Atlantic seabreeze progression.

FOG POTENTIAL AND OTHER REMARKS: Patchy inland this morning will develop near I-75. 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. GA...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 noon 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.