Area Forecast Discussion
Issued by NWS Jackson, MS
Issued by NWS Jackson, MS
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294 FXUS64 KJAN 180537 AAA AFDJAN Area Forecast Discussion...UPDATED National Weather Service Jackson MS 1237 AM CDT Wed Sep 18 2024 ...New AVIATION... .MESOSCALE UPDATE... Issued at 904 PM CDT Tue Sep 17 2024 Showers have diminished and skies are clearing across the area, perhaps a bit ahead of the computer guidance schedule. This could allow for a more robust period of fog development tonight as effective radiational cooling gets going. Most short term guidance is hesitant to produce widespread dense fog, so confidence is a bit too low to begin drawing up Dense Fog Advisories but that may be necessary as it becomes more clear which will win: radiational cooling or weak advection of drier air. Regardless, at least patchy areas of dense fog are expected tonight with lows in the lower 60s F north and upper 60s F south. /86/ && .DISCUSSION... Issued at 244 PM CDT Tue Sep 17 2024 Today... The forecast remains on track today: With our early morning fog burning off throughout the CWA and showers expected to develop across the southern half of the forecast area today. The primary driving mechanism for the weather today has transitioned from Francine remnants to the interaction between a continental ridge and a deep retrograding low centered over the eastern parts of the Carolinas. This pattern has created easterly flow in SFC-700mb level which will dry out the northern half of the CWA, inhibiting our rain chances in those areas. Conversely, the offshore stationary boundary to our south will allow for a moderate amount of isentropic lift, coupled with high amounts of surface level moisture from previous rainfall totals, will provide enough of the necessary ingredients for light showers south of I-20 today. Nothing to get too excited about though as projected totals for today are not expected to be that much. High relative humidity values and moderate cloud coverage are contributing to our smaller diurnal temperature swings, leading to cooler highs in the mid 80s F and seasonable lows in the mid 60s F. Winds are not expected to be particularly notable with generally calm easterly conditions persisting throughout today. Tonight through Friday Morning... The main focus from tonight through the short term period will be the formation and coverage of fog across the region. There is a plethora of low level moisture and with our cloud coverage clearing out a bit tonight, we will see more ideal conditions for radiational cooling tonight looks to be our most favorable setup for fog (some possibly dense) across the forecast area. While we have some confidence in the fog develop, enough uncertainty exists to hold off at this time on a dense fog advisory. We will message with a graphic indicating the fog potential for tonight. Next shift will evaluate and update accordingly. As we move through the rest of the work week we will continue to see a moderate amount of drying easterlies coming around the low over in Carolinas. That drying will dampen our fog coverage for the rest of the week, lowering density to an obscuration of between 3-5 miles for the area. Friday Afternoon through Tuesday... In the long term an upstream ridge will begin to build into the area, allowing for generally northerly flow and strong dry air advection. This dry air will curtail any chance for fog or mist development throughout the remainder of the period. In tandem with lower level drying, the ridge will bring mostly clear skies and more seasonal temperatures to the region: Highs in the low 90s F and lows in the upper 60s. Next week looks to be the last time we consistently breach 90s for the year as Autumnal climatology begins to take hold afterwards./OAJ/ && .AVIATION... (06Z TAFS) Issued at 1234 AM CDT Wed Sep 18 2024 With the exception of a period 09Z-14Z where MVFR/IFR vsbys wl be psbl, VFR conditions and a light wind will prevail through the TAF period. /22/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 66 89 65 89 / 0 0 0 0 Meridian 64 90 65 91 / 0 0 0 0 Vicksburg 67 89 65 90 / 0 0 0 0 Hattiesburg 69 92 67 93 / 0 0 0 0 Natchez 68 89 67 90 / 0 0 0 0 Greenville 63 87 64 88 / 0 0 0 0 Greenwood 64 89 65 90 / 0 0 0 0 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && $$ 86/OAJ/22