169 FXUS62 KMLB 042109 AFDMLB Area Forecast Discussion National Weather Service Melbourne FL 409 PM EST Sat Jan 4 2020 .DISCUSSION... ...Turning Much Colder Tonight Behind a Strong Cold Front... Currently...Prefrontal squall line pushing south of I-4 as of mid aftn. A few storms generating wind gusts arnd 40mph, localized storm damage reported in Okahumpka and Deland earlier today due to possible weak tornadoes. Sharp temp drop acrs the squall line... L/M80s ahead of it with record or near record readings, L70s behind it. SW winds gusting to 25-30mph with sfc dewpoints in the U60s/L70s. Windshift has reached GNV/JAX with dewpoints in the L60s, suggesting the fropa has pushed into the nrn peninsula but has yet to reach the I-4 Corridor. Tonight-Sunday...The squall line is expected to exit into the FL Straits around 00Z, followed by a reinforcing front that will sweep thru central FL by daybreak. Isold/sct shras lingering over the Space and Treasure Coasts into early evng, but should push south of central FL before midnight. Turning much colder overnight with min temps dropping into the L/M40s along and north of I-4...M/U40s Treasure Coast/Lake-O region...a temp whipsaw of 20-25F from this morning's mins in the U60s/L70s. Wind gusts diminishing by sunset, but a tight pgrad in the wake of the fronts will prevent the airmass from decoupling. Fcst winds overnight btwn 10-15mph may generate some wind chills in outlying areas north of I-4, but these would be brief and confined to the predawn hrs. Rapid clearing behind the front as winds veer to NW and produce a strong cold air advection pattern. High temps Sun in the L/M60s... about 5-10F blo avg. Sun night-Mon night...A high pressure over the northeast Gulf will take control of weather conditions during this period. PWAT values will be around a quarter of an inch, bringing RHs values to below 30 percent from northern Osceola northward towards inland Volusia and Lake County on Monday. Lows on Sun night will drop to the upper 30s from Volusia to inland Treasure Coast while Space and Metro Orlando could hold on to lower 40s. Treasure Coast meanwhile might drop to only the upper 40s. High temps will climb to the upper 60s to near 70 across east central FL and cool down again on Mon night to the low- mid 40s for northern Osceola northward and upper 40s- lower 50s for the Space and Treasure Coast. Tuesday-Friday (previous modified)...A weakening upper trough remains poised to push through a surface front across ECFL Tue night into early Wed morning, but moisture remains scant. Rain chances are forecast to be near none as in the latest model runs. Mostly dry for Wed-Thu, but models begin to bring deeper moisture back into the region on Fri as winds veer SERLY. Again, a 20pct chance or less for any light precip on Fri and on Sat. Temps near climo on Tue for highs in the L70s most areas, and then cooler again for Wed (post-frontal) in the M-U 60s, though perhaps only L60s north of I-4. Thu highs rebound again into the L-M70s with deeper onshore flow returning. Fri will be warmer yet in the U70s, but perhaps just M70s along the immediate Volusia/N. Brevard coasts. Lows generally 40s Tue overnight and a bit milder each night Wed/Thu overnight. Fri overnight into Sat morning will be in the 60s areawide with some L70s possible near the south Brevard/Treasure coasts.&& .AVIATION... Thru 05/18Z. Sfc Winds: Thru 05/00Z...W/SW bcmg W/NW 12-15KTS with fqnt sfc G21- 26KTS. Btwn 05/00Z-05/03Z...coastal sites bcmg W/NW 10-14KTS with ocnl sfc G18-22KTS...interior sites bcmg NW 8-12KTS. Btwn 05/12Z- 05/15Z bcmg N/NW 8-12KTS. Vsbys/WX/Cigs: Thru 05/00Z...SQLN S of KISM-KTIX to produce widespread IFR/areas LIFR cigs/vsbys in +shras. N of KISM-KTIX areas IFR cigs in -RA/RA bcmg MVFR cigs. Btwn 05/00Z-05/03Z...S of KVRB- KOBE slgt chc MVFR shras. Btwn 05/03Z-05/06Z bcmg VFR all sites. && .MARINE... Tonight...Initial cold front to push into the FL Straits by late evening, followed by a reinforcing front that also should clear the state by daybreak. Dangerous boating conds dvlpg as winds veer from W to NW, reaching near gale force with frequent gusts abv. Seas building to 6-8FT nearshore and 9-12FT offshore...up to 13FT in the Gulf Stream. Gale Watch all marine legs from 00Z/7PM Sun thru 15Z/10AM Sun. Slgt chc of shras thru mid even. Sun...Conditions slow to improve as high pressure pushes acrs the GOMEX and maintains a tight pgrad. Small Craft Advisory criteria expected to linger for much of the day. A fresh to strong N/NW breeze early in the day, diminishing to a moderate to fresh breeze by midday, then gentle to moderate by sunset. Seas 6-8FT nearshore and 9-12FT offshore early, subsiding to 4-6FT over the shelf waters and and 6-8FT over the Gulf Stream by sunset. Mon-Wed (previous)...Generally favorable boating conditions thru the day Tue as high pressure remains in control, but is abruptly shifted eastward with the approach of another front Tue overnight. Cautionary Statements for winds may be necessary Tue night offshore north of Sebastian Inlet as NW/N winds increase to 15-20 kts and further southward across the Gulf Stream during the day Wed with veering toward the NNE/NE, then ERLY Wed night as speeds remain elevated. Seas will remain favorable and approachable thru Tue evening, then will build 3-5 ft near shore and 5-6 ft Gulf Stream thru the day Wed, perhaps up to 7 ft over the Gulf Stream Wed overnight from Sebastian Inlet southward. && .FIRE WEATHER... Sunday-Monday (previous)...Latest model guidance coming in drier for these two days behind today's front. Expect min RHs in the 30s across the interior both afternoons. We should see cool wind chills early Sun morning, then perhaps some light, patchy frost late Sun night into early Mon morning. Initial winds Sun morning may approach 10-15 mph, but decrease thru the afternoon as the pressure gradient relaxes. ERC values remain fairly low for this time of year. Watch/Warning headlines not anticipated. && .PRELIMINARY POINT TEMPS/POPS... DAB 45 60 39 65 / 10 0 0 0 MCO 47 63 42 68 / 10 0 0 0 MLB 47 64 42 67 / 10 0 0 0 VRB 50 63 43 68 / 10 0 0 0 LEE 44 63 41 69 / 10 0 0 0 SFB 46 63 40 68 / 10 0 0 0 ORL 47 63 45 68 / 10 0 0 0 FPR 49 64 44 68 / 20 0 0 0 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...Lake Wind Advisory until 7 PM EST this evening for Coastal Volusia-Indian River-Inland Volusia-Martin-Northern Brevard- Northern Lake-Okeechobee-Orange-Osceola-Seminole-Southern Brevard-Southern Lake-St. Lucie. AM...Small Craft Advisory until 7 PM EST this evening for Flagler Beach to Volusia-Brevard County Line 0-20 nm-Flagler Beach to Volusia-Brevard County Line 20-60 nm-Sebastian Inlet to Jupiter Inlet 0-20 nm-Sebastian Inlet to Jupiter Inlet 20- 60 nm-Volusia-Brevard County Line to Sebastian Inlet 0-20 nm-Volusia-Brevard County Line to Sebastian Inlet 20-60 nm. Gale Warning from 7 PM this evening to 10 AM EST Sunday for Flagler Beach to Volusia-Brevard County Line 0-20 nm- Flagler Beach to Volusia-Brevard County Line 20-60 nm- Sebastian Inlet to Jupiter Inlet 0-20 nm-Sebastian Inlet to Jupiter Inlet 20-60 nm-Volusia-Brevard County Line to Sebastian Inlet 0-20 nm-Volusia-Brevard County Line to Sebastian Inlet 20-60 nm. && $$ Negron/Bragaw/Rodriguez/Weitlich