Area Forecast Discussion
Issued by NWS Jackson, MS
Issued by NWS Jackson, MS
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410 FXUS64 KJAN 021517 AAB AFDJAN Area Forecast Discussion...UPDATED National Weather Service Jackson MS 1017 AM CDT Thu May 2 2024 ...New MESOSCALE UPDATE... .MESOSCALE UPDATE... Issued at 1016 AM CDT Thu May 2 2024 Another challenging and complex forecast for the near term with poor guidance due to the meso-scale nature of the sensible weather. Morning analysis shows a warm frontal type feature across our S to W parts of the cwa, basically this is the mark of the better low level moisture return. This feature gets more messy as you go westward as we have a MCS established and has modified the boundary across SW LA into E TX due to convective outflow/cold pool evolution. Per 12z JAN raob analysis, moisture depth is rather low and we have poor lapse rates along with 3 noted inversion layers through 400 mb. Saying this, our forecast area will need much higher moisture advection to occur to support deep/strong convection along with an increase in stronger flow. This doesn`t appear to occur today and this is being realized by the MCS weakening as it propagates eastward. Hi-res guidance showed this evolution (despite errors in timing/location) for this morning into the afternoon with a weakening/decaying MCS. The quality lower level moisture advection is not really moving into the area from S LA as this area is generally limited in the 850mb theta-e. The best 850 theta-e air is back west across S and Central TX and if feeding into the back side of the decaying MCS. This configuration will only really support better storm activity well to our west. Due to these limiting factors, sever storm potential over our forecast area looks to be quite low and less than the advertised Marginal Risk. We will be collaborating to make adjustments this morning after more assessment from the 12z CAM guidance. The next main forecast challenge for today into tonight will be PoPs and weather. Will do my best to capture the timing of activity today, but much of the area will be moisture starved by later afternoon/evening and feel rain activity will be much harder to come by. The early take on the 12z CAMs supports much lesser rain chances for tonight...and if this holds, we will need to lower PoPs quite a bit. So, look for the forecast to be an evolving one to best capture trends. More info to come with the afternoon forecast package. /CME/ && .DISCUSSION... Issued at 401 AM CDT Thu May 2 2024 Today and Tonight: Continued warmer than normal through tonight despite an increase in cloud over and rain chances. Early morning surface analysis still had a ridge nosing into our CWA from the east. This was resulting in a southeast to south wind that was continuing to increase low level moisture back across our region. This moisture increase has led to the development of patchy dense fog and stratus across our southeast that is expected to increase in coverage across our south this morning. A Dense Fog Advisory is in effect until 9AM for the area along and south of a line from Laurel to Brookhaven where visibilities less than a quarter mile are likely. Regional radars were already lit up this morning with an area of convection over east Texas. A split flow regime will continue with the southern branch across the Gulf coast states. A disturbance within the southern branch will help drive this convection east today into our CWA. Model consensus suggests the convection will develop into a bowing line as it moves into our CWA during the heat of the day. The primary threat will be damaging wind gusts but hail to quarter size and a brief tornado our two will also be possible. Although isolated severe storms will be possible as far north as Cleveland the main area looks to be along and south of Interstate 20 and mainly during the afternoon into early evening. Locally heavy rainfall may also lead to some runoff issues in the typically poor drainage areas. The severe storm threat will end early this evening but rain chances will continue through the night as a cold front approaches from the northwest. /22/ Friday through next Thursday... By Friday morning, rain chances look to stick around as a weak shortwave allows a boundary to hang up across central MS just north of a high pressure in the off of the MS coast. This will keep higher rain chances in the forecast through late Friday afternoon. Scattered to numerous showers and storms are expected across central and northern Mississippi on Friday. Rain chances are expected to decrease by the late evening into the overnight period. By the weekend, low level southerly flow paired with a series of week shortwaves moving through the region will keep scattered to isolated rain chances in the forecast through Monday. Highs will remain in the lower to middle 80s through the weekend. By Monday, surface ridging will amplify over the southeast CONUS, bringing drier and warmer air into the ArkLaMiss. Southwest flow will keep the moisture at bay going into the new work week. Additionally, increasing heights will bring our first dose of summer- like temperatures into the region. Highs are expected to climb into the upper 80s to low 90s by mid-week. The next chance of rain looks to be north of the hwy 82 corridor by late week, but guidance is a bit uncertain on specifics as of now. /AJ/ && .AVIATION... (12Z TAFS) Issued at 650 AM CDT Thu May 2 2024 IFR/LIFR conditions wl prevail cntrl and south until after 14Z. By 15Z conditions wl improve to VFR and VFR conditions wl prevail through 18Z. After 18Z TSRA are expected to spread into the sw and affect HEZ. This activity will spread into cntrl and se MS TAF sites by 00Z Fri before dissipating. VFR conditions are expected this evening but IFR/LIFR cigs are expected to develop at most TAF sites by 08Z and continue through the end of the TAF period. /22/ && .PRELIMINARY POINT TEMPS/POPS... Jackson 85 68 80 64 / 60 50 60 30 Meridian 88 66 84 64 / 30 40 50 40 Vicksburg 83 68 79 65 / 70 50 70 30 Hattiesburg 88 67 84 65 / 30 40 40 20 Natchez 82 67 78 64 / 80 40 80 20 Greenville 84 69 78 66 / 60 80 80 40 Greenwood 87 68 79 65 / 40 80 70 40 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...None. LA...None. AR...None. && $$ CME/AJ/22