AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 1005 AM EDT Fri Jul 6 2012 DISCUSSION... The MCS that moved across our western zones overnight was exiting to the southwest this morning. There are currently only a FEW thunderstorms remaining over Walton county and the westernmost panhandle waters. For later this morning and afternoon, the CURRENT POP distribution looks good. See previous discussion for reasoning. The only concern is how much CONVECTION we will see west of the river in the WAKE of the MCS. Visible satellite imagery does show the skies already clearing over our SE AL zones so there will be plenty of INSOLATION. The 12z KTAE SOUNDING has a PW of 1.90" and is more unstable than yesterdays. The steering FLOW is once again very light so storms will be slow movers. && .AVIATION [through 12z Saturday]... Overall, VFR is expected to be the predominant condition for the bulk of the 24-HR period. MVFR in storms, with gusty winds to 20 or 30 knots possible in the strongest ones This afternoon. For now the TAFs reflect a VFR forecast with VCTS group at the time we think storms are most LIKELY. && .PREVIOUS DISCUSSION (524 AM EDT Fri Jul 6 2012)... .SYNOPSIS... The 03 UTC regional surface analysis showed a typically weak summertime PRESSURE pattern, with a lot of contamination from MESOSCALE convective systems (i.e. MESO highs and OUTFLOW boundaries). The main nearby synoptic features were the Piedmont TROUGH extending through central GA, and the West Atlantic RIDGE in the southern Gulf of Mexico. Although it is 0521 EDT, thunderstorms were still ongoing over our forecast area, which is unusual (except for this season). Vapor imagery and upper AIR data showed a maximum in the 500 MB HEIGHT field over MO, and a trough along the U.S. east coast. && .SHORT TERM... (Today through Sunday) Since none of the 00 UTC NWP guidance did an especially good job at initializing the late NIGHT/early morning thunderstorms, our forecast confidence for today isn`t all that strong. We`ll assume that the current storms and clouds will mostly dissipate by late morning, allowing plenty of time for daytime heating and sea breeze development. The combination of this sea breeze, the trough to our north, and any outflow boundaries or small scale MCVs from the current convection will contribute to convective initiation this afternoon and evening. Our PoP is an average of the GFS/NAM/EU MOS and local CAM PoP, and is generally around 40%. It`s not higher than that because there is some CHANCE that this morning`s clouds and storms could actually suppress later convection, and that the highest deep layer MOISTURE may begin transitioning west later this afternoon. It`s not lower than 40% because it`s still pretty moist and there should be a lot of mesoscale boundaries around today. While the weak winds aloft will prevent significant STORM organization (and WIDESPREAD severe storms), there could still be some strong to severe storms that are either PULSE type, or loosely- organized multi CELL type. Marginally severe HAIL and WIND gusts are the main threats, with the highest chances being this afternoon and evening. The global models show gradual drying from west to east in the MID TROPOSPHERE this weekend, which will allow for a gradual decrease in the PoP Saturday and Sunday from east to west. Highs will be in the mid 90s (inland) each day, and it will be humid. However, it doesn`t appear that heat index values will REACH" onClick="return popup(this, 'notes')">REACH ADVISORY levels through this weekend. .LONG TERM [Sunday Night through next Friday]... Not a lot has changed with the thinking in the extended forecast from this time last night. Large upper level ANTICYCLONE centered over the Upper Midwest in the short term period will be slowly retrograding by Monday into the Intermountain West. The accompanying large upper level ridge axis will get split by an amplifying trough in the eastern CONUS such that two highs emerge - the Bermuda HIGH to the east and the aforementioned one over the west. The digging SHORTWAVE that will be carving out the east coast trough should be embedded in the northern branch of the JET stream, and thus should be fairly progressive. Therefore, a broad mid-upper level trough is likely to become somewhat CUTOFF from steering flow and linger over the lower Mississippi River Valley. This is likely to allow a deep favorable FETCH of moisture to evolve from the deep TROPICS and Caribbean, with EASTERLIES over the Caribbean Sea rounding the western edge of the Bermuda High and generally southerly flow over the eastern Gulf of Mexico. Meanwhile, HPC forecasts and global model consensus place a stalling FRONT somewhere in the vicinity of the Gulf Coast states by later in the week. The combination of all these factors should lead to increasingly UNSETTLED weather, especially once the western edge of the Bermuda High begins to erode. Best RAIN chances look to be Wednesday to Friday and they were nudged more into the 40-50% RANGE in the afternoons based on the latest guidance. Increased cloudiness and rain should lead to cooler temperatures on average, so high temperatures were gradually trended down closer to 90 by the end of the work week. && .MARINE... Typically LOW summertime values of winds and SEAS are expected at least into early next week. && .FIRE WEATHER... No fire weather concerns for the next week AS relative HUMIDITY should remain at or above 40 percent.