textproduct: NWS Birmingham

KEY MESSAGES

Issued at 103 PM CDT TUE MAY 19 2026

- Warm conditions are expected again on Tuesday with highs near 90 degrees. Heat indices will remain in the upper 80s in the far north and lower 90s the rest of the area through much of the work week.

- Chances for showers and storms increase Tuesday afternoon and continue each afternoon through the weekend, with the highest (40-70%) chances in northern and western portions of Central Alabama during the afternoon and evening hours each day.

- High moisture levels will support periods of heavy rain, though total amounts are anticipated to be light (1 to 2 inches across the area).

DISCUSSION

(This afternoon through Monday) Issued at 103 PM CDT TUE MAY 19 2026

High pressure will develop and strengthen to the east of the southern US through the work week, putting AL on the western side of the center of the high. This will cause prevailing southerly flow, which will bring plenty of moisture to the state. A boundary will approach from the northwest, stalling as it moves into the northern counties. As the boundary meanders over the same general area for the next couple of days, it will bring enough forcing for diurnal convection each day.

Today, instabilities between 1000 and 2000 J/kg, with LI values in the -4 range could support afternoon thunderstorms, though moisture isn't as impressive, with PW values hovering just higher than the 75th percentile. CAMs are showing a slight increasing trend for an isolated cell activity, though if anything does form, it should be weak and short lived with the lack of moisture. A line of storms will approach the western edge of the state by this evening. CAMs are showing a general agreement that the line will weaken, with showers and maybe a rumble of thunder possible through much of the night. Activity could linger in the early morning Wednesday, but should be limited in coverage and strength. By Wednesday afternoon, greater instability, between 2000 and 3000 J/kg, with LI values up to -6, and PW values increasing to the 90th percentile could support greater storm development. Confidence is slightly lower on how strong these storms could be, with a lot depending on how great the coverage of storms is Wednesday early morning, and how much clearing will happen by mid to late morning. Wind profiles are weak, so any storm should be slow moving and pulse like. With PW values increasing, heavy rain and frequent lightning are possible, and any area that receives a slow mover may see a locally higher amount of rain totals.

Thursday and Friday have a greater chance for the diurnal afternoon convection developing and remaining through the early night. A low pressure begins to develop over the mid MS River Valley, with low and mid level winds increasing. With greater low level convergence expected along that stalled and weakening boundary, and closer to the low, coverage will be greater in the northwestern half of the state, with similar instability values, wind profiles, and LI values as Wednesday. Strong storms are possible with high rain rates, frequent lightning, and gusting winds in each storm. By the weekend, the low moves to the northeast, strengthening with time, and another low pressure approaches the state from the west. Diurnal convection should continue, with low level flow from the south keeping PW values elevated and plenty of moisture advection.

Throughout the week, an average of a couple of inches of rain could fall, with a gradient from northwest to southwest, higher values in the northwest closer to the greater focus of convection, and lower values in the southeast. However, because of the high PW values, slow movement of storms (at times), and the storms should become strong, areas that receive storms, or even training storms, will likely see much higher rainfall totals.

Temperatures will start off the week in the 90s, cooling slightly to the upper 80s. With the flow from the south and moisture advection, even though the temperatures may feel a couple of degrees cooler, the heat indices will remain in the upper 80s in the far north, and lower 90s through the rest of the area. Many days could feel stifling and with more activities outside, heat stress could occur quickly in those not taking proper precautions.

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AVIATION

(18Z TAFS) Issued at 103 PM CDT TUE MAY 19 2026

VFR conditions are expected through the 24 hour TAF period. Isolated to scattered diurnal convection is possible today, though confidence is too low on timing and coverage near any TAF site, so left mention out of each TAF for now. Winds will weaken overall for Wednesday, so left VRB in many TAFs from this evening through the end of the TAF period.

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FIRE WEATHER

Dry conditions are in store for much of the day Tuesday with minRHs in the 40-50% range during the afternoon. Southwest flow will bring more moisture, with RH values slowly increasing through the end of the work week. Isolated to scattered showers are expected, with a greater concentration in the north and northwest, beginning Wednesday afternoon and each afternoon into the weekend.

PRELIMINARY POINT TEMPS/POPS

Gadsden 66 87 64 86 / 0 60 40 60 Anniston 66 87 64 86 / 0 50 40 50 Birmingham 70 87 67 86 / 10 60 50 50 Tuscaloosa 70 88 67 86 / 10 50 60 40 Calera 68 89 65 88 / 0 40 50 30 Auburn 68 89 67 89 / 0 30 30 20 Montgomery 70 89 68 89 / 10 30 30 20 Troy 69 89 68 89 / 10 40 30 10

BMX WATCHES/WARNINGS/ADVISORIES

None.