788 FXUS62 KJAX 200500 AFDJAX Area Forecast Discussion National Weather Service Jacksonville FL 100 AM EDT Tue Apr 20 2021 .AVIATION... [Through 06Z Wednesday] Mainly VFR in the 06Z-12Z period with a slow increase in high clouds, but just enough low level cooling at the surface to support some "trashy" fog with possible MVFR VSBYS at VQQ in the 08-12z time frame. Clouds thicken up and lower quickly after 12z as moisture begins to over-ride the frontal boundary south of the TAF sites. For now expect SSI to remain VFR and rain-free with just some mid-high clouds through the period, while JAX/CRG/VQQ just north of the main rain shield and have just added a brief period of VCSH from 15-21z with mainly VFR CIGS around 4000 ft expected. Further south at SGJ/GNV expect about a 5 hour period of rainfall with MVFR CIGS around 2000 ft, from 16-21z at GNV and 17-22z at SGJ, then despite rainfall ending by 00z will leave some BKN MVFR CIGS at SGJ/GNV the remainder of the period. && .PREV DISCUSSION [908 PM EDT]... .NEAR TERM [Through Tonight]... Dry weather, clear skies, and mild winds will continue on into tonight as the last remaining showers have since moved off to the south with the advancing frontal boundary. Cloud cover is expected to increase overnight and into Tuesday morning as the boundary of dry air starts to retract northward. Significant overnight fog developments are not expected. High temperatures for today will be in the upper 70s today with overnight low temperatures dropping down into the 50s for inland areas and into the 60s for areas near the coast and along the St Johns River. .SHORT TERM [Tuesday Through Wednesday Night]... Dry air associated with high pressure ridging will briefly give way to showers and storms on Tuesday as a upper level shortwave trough moves over the Florida peninsula bringing convection primarily to areas south of the I-10 corridor and to counties adjacent to the coastline as the short wave progresses across the Florida peninsula and off to the northeast. Dry weather will return on Wednesday as ridging builds back in over the forecast area, following the passage of the short wave trough. Daily high temperatures during this period will rise from out of the 70s on Tuesday up into the the lower 80s on Wednesday as clear skies return. .LONG TERM [Thursday Through Monday]... Influence from high pressure ridging over the region will begin to weaken on Friday as the center of high pressure moves off towards the northeast, shifting the prevailing flow to become more out of the southwest bringing in increased cloud cover and chance for evening showers. A trough ahead of an advancing cold front is expected to move across the southeastern US at some point during the weekend, with models currently showing disagreement as to the exact timing and placement of the trough. However, showers and potentially strong storms are anticipated for the weekend with conditions becoming more dry and stable the following week. Temperatures are expected to be relatively close to the seasonal average during this period. .MARINE... The frontal boundary will continue to move south across the region today, with high pressure building in from out of the north. The boundary will lift back to the north overnight and into Tuesday. This boundary will slip back to the south Tuesday night. Another cold front will move southeast across area Wednesday into Wednesday night. High pressure will build to the northwest Thursday, then north northeast Friday. The high will move more toward the east Friday night as a warm front lifts northeast across area. A cold front will move southeast across region Saturday night into Sunday. Rip Currents: Moderate Risk for NE Florida thru Tuesday. Minor Risk for SE Georgia today and Moderate Risk on Tuesday. .HYDROLOGY... Dry weather today will help mitigate flooding concerns, but another round of rain is expected on Tuesday. Minor River flooding may still be possible along the upper Santa Fe Basin, but greatest flooding impacts will continue to be the metro areas mainly south of Jacksonville through Tuesday. && .PRELIMINARY POINT TEMPS/POPS... AMG 53 79 43 70 45 / 0 10 0 0 0 SSI 60 81 52 68 55 / 0 20 10 0 0 JAX 59 82 50 70 53 / 10 30 10 0 0 SGJ 61 81 57 68 58 / 10 40 20 0 0 GNV 57 81 51 74 52 / 20 50 10 0 0 OCF 60 83 53 76 55 / 30 60 20 0 0 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AM...None. &&