textproduct: Jackson

KEY MESSAGES

- Heat and humidity more typical of early summer can be expected along with increasing thunderstorm chances next week.

DISCUSSION

Issued at 335 AM CDT Sun May 17 2026

Through Tonight: After a brief period of patchy fog this morning in the southeast, rain chances return to our southwest by afternoon. Otherwise, warmer than normal temperatures are expected through the period. Early morning surface analysis had a >1015mb ridge nosing across our CWA from the east and a <995mb low over the central Plains. The surface ridge will actually strengthen over our CWA through tonight while the surface low tracks to the north. Thanks to upstream troughing within the southern branch of the jet stream our winds aloft will become southwesterly today. Together these features will work to increase deep moisture over our CWA from the southwest today. The 00Z Sun JAN sounding only had a PWAT of 0.91in as result of a very dry layer at 850mb along with a formidable cap also at 850mb. Models suggest that by this afternoon PWATs will be back above 1.75in over our southwest with little to no cap and temperatures climbing through the 80s. The heating of this moisture increase will lead to a few showers and thunderstorms over the southwest that may spread into the northwest and central portions of the CWA before dissipating rapidly after sunset. The convection today is not expected to become severe. Although the convection will be diurnally driven, cloud cover will continue over the western half of the CWA tonight while much less cloud cover is expected in the east. Patchy light early morning fog can be expected in the southeast again but a south wind and cloud cover will hold temperatures well above normal in the west. /22/

Monday through Saturday...

This week (Monday through Thursday): Cold core low, developing over the Four Corners, will eject into the northern Plains to Great Lakes and into Canada and Hudson Bay region. Persistent seasonable warmth (4F to 8F above and highs in 86F to 91F) and moisture (1.5 to 2 inches) will be the norm. Summertime pattern is on tap for the work week. Rain and storm coverage will be scattered (20 to 45 percent Tuesday climbing into the 65-75 percent range across northern half Wednesday before settling back in to the 40-50 percent range through Saturday). There does not appear to be strong possibility of drying out until some time next week, so get those raincoats out and take other needed precautions!

Rain totals don't look particularly worrisome however with such a prolonged period of steady rainfall, an isolated cell overachieving could produced localized flash flooding; particularly in urban or otherwise nonporous locations so take heed.

Rising heat and humidity are going to bring about a more summertime feel with sites climbing into the mid to low 90s by mid week, which brings us to our next point:

Increased heat and humidity as well as lapse rates (vertical totals near 27C to 29C), some strong to isolated severe cannot be ruled out into early to mid week. A stronger wave swings into the Great Lakes and surface low ejects into eastern Canada (995mb to 1000mb), front will shift south southeast towards the Gulf states. A southern stream shortwave will enhance upper diffluence, increasing ascent and moisture advection. This will provide those higher range chances like mentioned above. High temperatures will be seasonable, with lows less seasonable, falling from 8F to 12F above (upper 60s to low 70s west) to 4F to 8F above (mid to upper 60s). With less seasonable temperatures, humidity and lapse rates, some stronger storms remain possible and while a few marginally severe storms cannot be ruled out. Rain totals for the week will be around a couple of inches (1 to 3 inches), which will help lessen some long term drought concerns. /OAJ/

AVIATION

(12Z TAFS) Issued at 633 AM CDT Sun May 17 2026

The lower flight restrictions have not developed and VFR conditions are expected to prevail areawide until after 20Z when TSRA may affect HEZ until 01Z. Otherwise, VFR conditions wl continue after 08Z when MVFR/IFR cigs wl develop cntrl and south and continue through the end of the TAF period. A gusty south wind to 20kts wl develop at GLH by 17Z and continue until subsiding by 02Z Mon. /22/

PRELIMINARY POINT TEMPS/POPS

Jackson 87 69 88 72 / 30 10 10 0 Meridian 87 65 88 69 / 0 0 20 0 Vicksburg 87 71 89 72 / 30 10 20 10 Hattiesburg 86 67 88 70 / 10 0 30 0 Natchez 87 72 89 73 / 50 20 20 10 Greenville 90 72 90 73 / 20 10 10 20 Greenwood 89 71 89 73 / 0 10 10 10

JAN WATCHES/WARNINGS/ADVISORIES

MS...None. LA...None. AR...None.