Heavy-rain outlook shifts from Texas Thursday to Arizona Friday

Thursday · West and Central Texas

Read the rain-rate forecast as a hazard clue, not a guaranteed total

WPC says the setup could support convective rain rates of about 1.5 to 2.5 inches per hour. That is a forecast of possible local intensity within storms—not a promise that every location will receive that amount or rate.

The WPC excessive-rainfall discussion forecasts a corridor of 2 to 4 inches, with locally higher amounts possible, between the Stockton and Edwards Plateaus and the Midland area. Placement and totals can still change as the event approaches. Repeated storms, fast rainfall over an urban drainage, and rain over already wet ground can create impacts that a regional total alone does not show.

A rainfall forecast describes what may fall. It does not say a particular road is open, and it is not a stream observation or a Flash Flood Warning. Check the issue time, valid period, and exact map before using any screenshot in a plan.

Friday · Central and Southern Arizona

Terrain, burn scars, washes, and recent rain can concentrate the risk

WPC expects Pacific moisture and thunderstorms to increase across the Desert Southwest Friday, with the strongest flash-flood signal over Central and Southern Arizona.

The national discussion specifically flags urban drainages, low-lying areas, small streams, narrow canyons and gullies, and burn scars as vulnerable places. A storm that is miles away can send water and debris into a normally dry wash or canyon. Never enter a flooded wash, road, or low-water crossing to test its depth or speed.

The Slight Risk does not mean every part of Arizona will flood. It means the WPC assessment supports a more organized risk of rainfall exceeding local flash-flood guidance within the outlined area. The local forecast and alert polygon answer the next, more specific question.

Official products · Different decisions

Outlook, forecast, watch, advisory, and warning are not interchangeable

Excessive Rainfall Outlook

WPC’s broad planning map shows the risk that rainfall will exceed flash-flood guidance at a point during the valid period. It is not a local alert and does not guarantee a flood at one address.

Rainfall forecast

Predicts rain amount, timing, or intensity for a stated place and period. Forecast values can change and do not prove a road or trail will remain safe.

Flood Watch

Flooding is possible. Review routes, charge devices, know higher ground, and be ready to change plans if a warning is issued.

Flood Advisory

Lower-severity flooding may still disrupt travel or create dangerous conditions. Read the affected area, timing, and action statement.

Flash Flood Warning

Flash flooding is imminent or occurring in the warned area. Move away from flood-prone locations and follow the warning’s instructions; never drive through floodwater.

A national outlook supports early planning. A local warning should drive immediate action. If a warning includes your location, use the warning—not an older forecast map or social post—to decide what to do.

Before a drive, hike, or outdoor shift

Move from the national signal to the exact place and hour

1. Open the newest WPC map. Confirm the day, issue time, valid period, and whether the route is inside the risk area.
2. Check the exact NWS point forecast. Read the timing, rainfall wording, thunderstorm chance, and overnight period—not only the daily icon.
3. Check alerts for the whole route. A destination forecast does not describe every low crossing, canyon, urban underpass, or county along the way.
4. Identify higher ground before rain begins. Do not wait for water to enter a wash, campsite, or low road before choosing an exit.
5. Recheck immediately before departure. Forecast placement and local alerts can change after this article was published.