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

- Windy with Strong to Severe TStorms This Afternoon & Evening. Wind Advisory for Northeast FL and much of Southeast GA This Afternoon. Squall Line of Strong to Severe Storms Traverses our Area. Hazards: - Wind Gusts of 50-70 mph - Isolated to Scattered Tornadoes - Lightning - Small Hail

- Extreme Drought Expanding Across our Region. Moderate Wildfire Danger Today for Portions of Northeast FL. Gusty Winds Today will Potentially Enhance the Spread of Existing Wildfires. Lightning from TStorms This Afternoon Could Cause Additional Wildfire Ignitions

- Small Craft Advisory Today through Early Monday Morning

- Moderate Rip Current Risk at Area Beaches

UPDATE

Currently monitoring an intensification trend in convection moving eastward across the western Panhandle of Florida, which has become more linearly organized over the last hour. This squall is forecasted to continue to intensify as it moves toward the region through the rest of the morning with increasing risk of embedded severe segments and quick-developing circulations possible along the line as it approaches and pushes into the region.

The main hazards today will be along the squall line where the modestly unstable atmosphere and high-shear environment will certainly increase the risk of damaging wind gusts along the line where bowing segments could produce gusts up to 70 mph. While damaging winds are the more widespread risk, there is also the potential for a few to scattered quick spin- up tornadoes along the line, especially at inflections along the line where augmented inflows regions (south- southeasterly surface winds) form. Though small hail is more likely given the lack of supporting buoyancy aloft, if surface temperatures warm a few degrees warmer (reaching the low 80s) than forecast, the steep lapse rates aloft and lengthy hodographs may support marginally severe hail.

As far as timing is concerned, it appears the current position of the line is moving faster than the fastest CAM guidance at the moment (HRRR). Due to the slower model bias, pops were nudged to likely/categorical levels slightly earlier for portions of SE GA, now reaching the Ocmulgee River around noon. The broadening warm sector will also support fast-moving cells out ahead of the main line and those "seedlings" may begin to sprout up around 10 AM across SE GA and could produce gusty winds before the main convective event arrives. Otherwise, the main squall line will race southeastward across the area, exiting to the southeast around 6-8 PM this evening.

A Windy Advisory remains in effect across NE FL and portions of SE GA this afternoon. The heaviest non-thunderstorm winds will focus along the I-75 corridor where a strong low-level jet (supporting the high-shear environment) noses in from the northeastern Gulf with winds around 50 kts (60 mph) only 2k ft off the surface. Likely to see strongest gradient wind gusts between 1-5 PM with gusts up to 45 mph.

Please stay aware of the weather today as a Tornado Watch may be issued later after coordination with the Storm Prediction Center.

NEAR TERM /THROUGH TONIGHT/

A strong and positive tilted mid-upper level trough will move through the southeast CONUS today, with a surface low around 1006 mb and cold front marching through the southeast states. Moderate to strong height falls at 500 mb of 50-100m, which will support good ascent over the region. Ahead of the system, a moderate to strong pressure gradient is anticipated as a weak warm front lifts up north of the area by late morning. Southerly winds pick up to 15-25 mph with potential gusts of 35-45 mph. Wind advisory continues and expanded a bit given some of the guidance and to cover the potential today. Warm temps expected in the upper 70s to lower 80s with a record high, possibly tied at JAX today.

Ahead of the cold front, all CAM model guidance show a squall line holding together as it traverses the southeast and the Gulf coast, and timing shows it moving into our western zones between 2-3 pm, middle portions around 4-5 pm, and southeast portions around 7-8 pm. Typical low CAPE, high shear environment with bulk shear of about 50- 55 kt that will be conducive to locally damaging wind gusts and a couple of brief tornadoes both ahead of and within the QLCS system. The 0-3km shear values of at least 25-30 kt are favoring some bowing segments within the line and thereby enhancing brief spin-ups. Not particularly favorable for large hail given the directional shear is not strong aloft. Scattered convective showers expected after the passage of the squall line through late evening as the potent trough swings through the area. Lingering isolated showers still possible after 2-3AM but overall drier air will start to filter in through the overnight period. May be some low clouds and light fog develop especially over southeast GA by early morning. Lows tonight in the 50s most areas.

SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/

Monday, a strong southern stream mid/upper level shortwave trough exiting off the southeast coastline will merge with a northern stream trough and deepen as it moves off the Mid Atlantic coast as ridging aloft arrives over the lower MS valley to the central appalachians. This pattern will support somewhat drier northerly flow filtering into the area as a strengthening surface low departs northeastward from the Carolina Outer Banks while high pressure builds to our north across the OH/TN river valleys. A weak surface trough will extend over NE FL behind an exiting cold front and allow for isolated Showers to persist into the afternoon hours before moving out into the Atlantic by the evening hours. Northerly winds will turn northeasterly by late afternoon and cloudy skies will a trend to clearing skies. Cool air advection will limit highs to near normal along the coast in the and a little above normal over inland NE FL with upper 60s to low 70s. Monday evening, high pressure will shift over the appalachians into eastern NC/VA and cool northeasterly flow will continue overnight. This will keep a few clouds near the coast as a weak coastal trough produces Atlantic stratocumulus clouds that occasionally will move onshore while staying mostly clear further inland. Lows will range from the low 40s over inland SE GA to the upper 40s along the SE GA coast and NE FL with low 50s along the St Johns river basin and the NE FL coast.

Tuesday, as ridging aloft moves into the southern Appalachians and Mid Atlantic region, surface high pressure will stretch from southeast VA to central SC early in the day and then sink south of the NC/SC coast in the afternoon. Light easterly winds will become southeasterly well inland under mostly sunny skies. Onshore flow over the cooler shelf waters will limit highs to only the mid/upper 60s along the coast and rise to the low/mid 70s west of I-95.

Tuesday evening, the high will move away into the Atlantic waters more to our east. Thin high level clouds will increase overnight and the moist low level flow will support at least patchy fog potential given the light winds. Lows will fall into the low 50s along the coast and upper 40s to near 50F inland.

LONG TERM /WEDNESDAY THROUGH SATURDAY/

The period will feature broad ridging stretching from across the FL peninsula from the west central Gulf waters midweek, then shifting eastward from the the Bahamas to Cuba on Saturday as troughing over the western US deepens and moves northeastward to the upper Midwest and Great lakes Friday into Saturday. This pattern will allow for surface high pressure to develop near Bermuda with a surface ridge axis extending over the central FL peninsula south of our area midweek, then begin to nudge further south and east by Friday as a cold front sinks towards the area from the northwest. Ahead of this front, scattered afternoon showers may develop across SE GA Friday into Saturday.

The influence of the high pressure will allow for warmer days with low potential for reach daily record highs (see climate section) and partly cloudy skies with daily seabreezes and southwest flow that will push the Gulf seabreeze well inland while pinning the Atlantic seabreeze near or off the coast. Southwest flow aloft will also increase moisture levels back to near normal/slightly above normal PWAT levels 0.75 and 1.0 inches, which will support dewpoints rising to the low 60s over NE FL and near 60 over SE GA. As a result, overnight fog/low stratus potential will increase from the Gulf coast with sea fog likely remaining offshore over the coastal Atlantic waters due to the the southwest flow.

Temperatures will begin around 10 degrees through the week and trend 10-15 degrees above normal into the start of next weekend.

AVIATION /12Z SUNDAY THROUGH 12Z MONDAY/

Multilayered clouds this morning with primarily VFR clouds. A strong cold front and associated pre-frontal squall line is expected to move in between 20z and 01z across the airport sites. Showers and embedded thunderstorms are expected, some of the which could be strong to severe. Expect reductions in cigs and vsby as this squall moves through today with MVFR, and brief period of IFR cig/vsby. VCSH or patches of rain expected from 01z to 06z, with VCSH thereafter. Preceding the incoming squall line, strong south and southwest winds ahead of the front are forecast to develop with gusts between 25-35 kts at area terminals. The strong winds gusts should abate by 01z tonight as the line of convection passes to the east of the terminals. Still some breezy southwesterly winds are likely after 01z-02z tonight.

MARINE

A strong low pressure system will move across the southeast states today with an associated cold front and pre-frontal squall line expected late this afternoon and evening. Strengthening south winds and building seas today will support Small Craft Advisory across all waters with potential for gale force gusts. The cold front associated with the low will send the squall line of showers and thunderstorms through the waters late afternoon and evening. A few strong to severe storms are possible with this line of storms. High pressure ridging will then build back down the southeast coast on Monday before weakening and shifting east of the Florida Peninsula once again mid week.

Rip Currents: Moderate rip current risk is highlighted in the SRF today with a strong southerly winds expected, creating an increased longshore current flowing north. Persistent moderate risk likely for Monday as well, but some enhanced northeast wind may support a low-end high risk for northeast FL beaches.

FIRE WEATHER

- High Daytime Dispersions Area-Wide Today - Line Of Strong To Severe Thunderstorms Arrive This Afternoon

Approaching strong low pressure system and cold front will create strong south to southwest winds 15-25 mph with gusts to 35-45 mph ahead of a broken line of strong to severe T'storms that will move west to east across the area this afternoon into early evening. The strong transport winds will create high daytime dispersions over the entire area. Wind gusts may help increase spread rates from any existing wildfires despite MinRH values staying well above critical levels today. Some of these storms later today have the potential to create damaging wind gusts and isolated tornadoes. rainfall amounts will generally be around 1 inch with locally higher totals of 2-3 inches. Isolated shower chances remain on Monday, but decrease in the afternoon as drier air filters in. Dry conditions will prevail midweek as high pressure shift from just north of the area Tuesday with light easterly winds to east of the area Wednesday into Friday with south to southwest breezy winds in the afternoon and daily Gulf seabreeze developing and moving well inland during the afternoon hours.

FOG POTENTIAL AND OTHER REMARKS: Significant fog is not expected over the next few days. Patchy fog development will return each morning starting midweek next week.

CLIMATE

Record High Temperatures today into next week.

February 15: KJAX: 83/2001 KCRG: 84/2001

February 19: KAMG: 82/2018

February 20: KJAX: 86/1961 KGNV: 86/2019 KAMG: 83/2014 KCRG: 83/2014

PRELIMINARY POINT TEMPS/POPS

AMG 74 53 67 43 / 100 60 10 0 SSI 70 55 63 49 / 90 80 20 0 JAX 81 57 68 47 / 90 80 20 0 SGJ 79 57 67 51 / 80 90 30 10 GNV 81 58 72 48 / 90 80 20 0 OCF 81 58 73 49 / 80 90 10 0

JAX WATCHES/WARNINGS/ADVISORIES

FL...Wind Advisory from noon today to 6 PM EST this evening for FLZ021-023-024-030-031-035-038-120-124-125-132-136>138- 140-220-225-232-233-236-237-240-322-325-333-340-422-425- 433-522-533-633. GA...Wind Advisory from noon today to 6 PM EST this evening for GAZ162-163-165-166-264-350-364. MARINE...Small Craft Advisory until 10 PM EST this evening for AMZ450- 452-454. Small Craft Advisory until 8 AM EST Monday for AMZ470-472-474.