Marine Weather and Tide Forecast for Byram, MS

DISCUSSION
Issued at 131 AM CDT Thu May 21 2026

Today and Tonight:

Longwave trough to ridge pattern of the CONUS will keep rain in the ArkLaMiss region. A shortwave disturbance moving across Lower MS Valley will filter in additional moisture into the area, resulting in PW values in the 99th percentile. Widespread showers and storms are expected through the evening. With PW values in the 99th percentile, ample moisture transport, and storm training, flash flooding will possible today in areas receiving heavy rainfall. /SW/

Friday through next Wednesday...The primary focus through the mid and extended portions of the forecast will continue to be that of multiple bouts of rainfall affecting the area. Under persistent southwesterly to southerly flow across the region, multiple disturbances aloft will traverse the forecast area through the Memorial Day weekend into the middle of next week. These disturbances, coupled with the warm and abundantly moist airmass in place across the area, will yield multiple bouts of moderate to occasionally heavy rain falling across the forecast area during this time.

As rainfall continues to accumulate across the area during this time, in addition to just the daily potential for high rainfall rates over a short amount of time in localized areas, the threat for flash flooding could begin to become a concern. This will need to be monitored, with flooding hazards potentially being added to the HWO for portions of, if not all of, the forecast area through this forecast period. Otherwise, expect muggy conditions overall with near seasonable highs for this time of year. However at night, expect above normal lows. /19/

AVIATION
(12Z TAFS)
Issued at 624 AM CDT Thu May 21 2026

Morning showers with an isolated storms are moving across sites resulting in a mix of current flight conditions. Patchy fog will be possible through 14Z. As ceilings improve, flight conditions will return to VFR. Additional showers/storms are expected through the evening, lasting through the rest of the period. Flight conditions are expected to vary between MVFR/IFR flight conditions due to rain and low ceilings. /SW/

PRELIMINARY POINT TEMPS/POPS
Jackson 82 69 81 69 / 70 70 80 50 Meridian 83 69 82 70 / 80 60 100 60 Vicksburg 82 68 81 69 / 80 80 100 30 Hattiesburg 84 70 83 70 / 80 60 100 60 Natchez 84 69 82 70 / 80 80 80 30 Greenville 81 68 81 68 / 60 90 80 40 Greenwood 82 68 81 68 / 80 80 90 50

JAN WATCHES/WARNINGS/ADVISORIES
MS...None.
LA...None.
AR...None.