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

- Several Freeze Events through Early Next Week. Friday Morning: Hard Freeze Inland & Coastal Light Freeze Likely

- Dangerously Cold Wind Chills in the teens to low 20s Possible. Consecutive Nights of Inland Freezes Fri Night through Next Tue Night

- Small Craft Advisory & Gale Force Gusts Thu & Thu Night

NEAR TERM /THROUGH TONIGHT/

This afternoon...Partly sunny skies with temps closer to seasonable values for mid January in the lower 60s SE GA and mid/upper 60s for NE FL and around 60F for Atlantic Coastal Areas. North winds much lighter than yesterday around 10 mph or so.

Tonight...Increasing cloudiness from the south and west overnight as a broad surface forms offshore of the FL Atlantic coast as a longer wave mid/upper level trough deepens across the western Gulf. Min temps not as cool with lows in the mid/upper 30 across inland SE GA and 40s to lower 50s elsewhere and will likely bottom out around midnight to 3am then hold steady or even nudge upwards towards morning as clouds continue to increase, which should also prevent any significant fog formation. A few light showers and sprinkles will also be possible overnight mainly across northeast Florida as the surface low that develops near the southeast FL Atlantic coast tracks northward, east of the local area, into early Wednesday morning.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/

An upper level shortwave will quickly traverse across the region on Wednesday afternoon and evening, just a piece of energy associated with a deepening longwave trough over the south/central US. Despite the mid and upper level forcing, rain chances with this feature will be quite limited given the ongoing drought as well as limited layer moisture. However, a few light showers/sprinkles will likely traverse from west to east during the afternoon and evening, with rain chances around the 15 to 20 % range. With plenty of cloud cover and this feature acting as a weak pseudo cold front, high temps will be a bit cooler on average area wide: ranging from the mid to upper 50s over interior southeast GA to the low to mid 60s elsewhere. Main portion of the deepening/southeastward digging upper trough moves towards the area Wednesday Night and across the region through Thursday, with an accompanying strong cold front traversing eastward out ahead of the feature. Timing of the frontal passage is generally as follows: entering southeast GA around late Wednesday Evening, towards the I-10 corridor by about early morning Thursday, then clearing the entire region by about mid to late morning Thursday. Along with strengthening/gusty northwesterly winds behind the front during the daytime, a few showers will be once again possible overnight Wednesday and through the first half of Thursday, mainly across northeast FL where just a bit more moisture advection will be expected off the Gulf. Though overall, similar to Wednesday, moisture is quite limited despite the rather impressive forcing aloft, and combined with the mostly non-diurnal timing of the boundary, rain chances will therefore be limited to about the 30-50% chance at most for northeast FL and very low across southeast GA as much drier air starts to advect into the early throughout the morning hours. As expected, Thursday will be a much cooler day with the front moving through during the first half of the day, with upper 40s to low 50s north and west and mid to upper 50s south and east.

Thursday Night will feature clouds continuing to exit the area with a cold night in store. Thursday Night will be tricky with respect to both ambient min temperatures as well as apparent temps/wind chills, as it will highly depend on how quickly gusty northwesterly breezes subside as surface high pressure will start to center closer to right over the area by sunrise Friday Morning. Overall, both frost/freeze and Cold Weather Advisory products will be in play to Thursday Night and Friday Morning, which will continue to be evaluated through tomorrow. Though generally speaking, a hard freeze is likely inland with highs in the 20s, and in the upper 20s to low 30s closer to the coast and St. Johns Basin which very much keeps frost/freeze potential in the discussion all the coast.

LONG TERM /FRIDAY THROUGH MONDAY/

Cool high pressure will remain across the region on Friday before scooting off to our east Saturday as another frontal system approaches the region. This next cold front looks to move through the region Saturday Night into Sunday Morning, which once again looks like a mostly dry frontal passage. Dry high pressure is then expected to remain in place Sunday afternoon through the start of next week, remaining west or northwest of the region which will keep a cool continental drainage type flow in place. Aside from a bit of a "warmup" Saturday as the next frontal approaches and moves through, temps below normal will be expected for most of the long term. This will include chances for frost/freeze products each morning inland, and perhaps even closer to the coast Monday Morning.

AVIATION /18Z TUESDAY THROUGH 18Z WEDNESDAY/

Mainly VFR conds through the afternoon with SCT-BKN clouds around 5000 feet or so along with North winds in the 5-10 knot range. These conditions will continue this evening, with increasing clouds in the mid levels through the overnight hours, along with low probs of MVFR CIGS towards sunrise at NE FL TAF sites and will trend in this direction in the next TAF package. Low rainfall chances at NE FL TAF sites in the 20-30% range by the 12-18Z time frame, but will likely leave out of the TAF forecast for now.

MARINE

A coastal trough over the waters breaks down this afternoon and shifts farther offshore as high pressure builds across the the Gulf coast states. The high will extend across the local waters tonight into Wednesday as a broad surface low tracks northward well east of the local Atlantic coast. Westerly winds increase Wednesday night as a strong cold front moves across the region. Small craft advisory conditions return Thursday trailing the frontal passage and continue into Thursday night. Winds and seas subside Friday as high pressure builds directly over the local waters. The high will shift southeast Saturday as a weaker, dry cold front moves across the waters with a surge in northwest to north winds behind the frontal passage late Saturday into Sunday.

Rip Currents: SE GA Low Wednesday NE FL Low Wednesday

FIRE WEATHER

-Areas of low dispersions Today -Areas of high dispersions Thursday

High pressure over the southeast US will sink southward into the Gulf today, keeping winds generally out of the north to northwest. Winds will be strongest near the coast and St. Johns River Basin thanks to a coastal trough that will weaken throughout the day. Winds above the surface and therefore transport winds will be weak today, resulting in mainly low/poor daytime dispersions today. Lingering dry airmass will create MinRH values of 22-27 percent over inland Georgia northwest of about US84. Wednesday, west-southwest winds increase ahead of an approaching front resulting in good dispersions. Light scattered showers will be possible as a weak front moves through the area Wednesday into Wednesday night, though Thunder is not expected. Breezy northwesterly winds develop in the wake of the front bringing high dispersions area-wide on Thursday. A cold and dry airmass filters in for the end of the work week lowering RHs into the 20s. Elevated Fire Danger will be possible for inland southeast Georgia on Thursday due to breezy winds and low RHs.

FOG POTENTIAL AND OTHER REMARKS: Significant fog is not expected over the next several days. A widespread freeze is forecast for Thursday night, including areas of frost as well. A light inland freeze will be likely each night for several nights beginning Friday Night.

PRELIMINARY POINT TEMPS/POPS

AMG 62 36 57 36 / 0 10 30 10 SSI 60 44 61 42 / 0 10 20 10 JAX 64 45 64 42 / 0 10 20 10 SGJ 64 49 65 47 / 10 30 20 30 GNV 66 47 66 44 / 0 10 20 30 OCF 68 49 67 45 / 0 20 20 50

JAX WATCHES/WARNINGS/ADVISORIES

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