Polo has dissipated, but the flood threat has not ended. The National Hurricane Center issued its final advisory on the storm Tuesday evening, September 29, after it broke apart over northwestern Mexico. Its last discussion warned that the remaining moisture could still produce heavy rain and flooding in the southwestern United States and Southern High Plains. A storm losing its circulation does not mean its rain has disappeared. (NHC final Polo discussion)
As of Wednesday morning, September 30, attention is shifting toward Texas, Oklahoma, the Central Plains and the Corn Belt. The Weather Prediction Center has placed portions of those regions in a Moderate Risk of excessive rainfall, with another round of heavy rain expected in parts of the Southern Plains on Thursday. These are regional forecasts, not a prediction that every property inside an outlook area will flood. (WPC September 30 forecast discussion)
Forecast basis: This report uses the WPC discussion issued at 4:04 a.m. EDT on September 30, 2026. Forecast boundaries and local warnings can change during the day. Check the latest official forecast for your address before making travel or property-protection decisions.
What has already happened in the Southwest
Flooding has already disrupted roads and prompted rescues in the Southwest. The Associated Press reported flooded highways in New Mexico, water rescues in Arizona, and flash flooding near Zion National Park in Utah. Concerns about a possible dam failure also prompted evacuation instructions in several New Mexico communities. That reporting describes a potential failure, not confirmation that a dam failed. (AP reporting via NPR)
Those impacts are distinct from the rain still in the forecast farther east. Do not treat this article as a live evacuation map or assume an earlier order has been lifted. Follow your local emergency-management office and National Weather Service warnings; the NWS flood-safety guidance stresses avoiding floodwater and leaving immediately when water begins to rise.
Where the rain threat is moving next
The forecast is not one uniform rain total spread across several states. Different areas face different timing, and repeated storms can leave one community much wetter than another nearby. The regional breakdown below follows the September 30 WPC discussion.
- Southern Rockies and Front Range, Wednesday: Parts of southern Colorado, northern New Mexico and nearby mountain ranges could receive another 2–4 inches, locally higher. WPC identifies morning and evening periods of heavier precipitation and notes that already moist soils increase the flash-flood concern.
- Texas and Oklahoma, Wednesday afternoon into Thursday morning: Storms are expected to develop in western areas by late afternoon, then broaden and move east through the night. The forecast highlights West Texas, the Red River Valley and parts of central Texas. Local totals above 5 inches are possible in the heaviest pockets; that is not a statewide forecast.
- Central Plains and Corn Belt, Wednesday afternoon through early Thursday: The corridor from northern Kansas through parts of Nebraska and Iowa faces generally 2–4 inches, locally as much as 6 inches. WPC expects some of the strongest rain to reach western and central Iowa after nightfall, with storms potentially tracking repeatedly over the same areas.
- Southern Plains, Thursday: A Moderate Risk continues from parts of South Texas toward southeastern Oklahoma. The Hill Country and I-35 corridor are particular concerns, with 2–4 inches, locally higher, forecast in the Hill Country. The discussion calls for rainfall rates commonly reaching 1–2 inches per hour in the heavier storms.
- Southern Texas, Friday: Additional rain may fall over ground already affected by earlier rounds. WPC maintains a Slight Risk there for Friday into early Saturday. A lower outlook category should not be read as an all-clear for an already flooded road or neighborhood.
Why a storm that dissipated can still matter inland
The useful distinction is between the storm's organized circulation and the moisture it leaves behind. NHC ended Polo's advisories because the cyclone dissipated; its final discussion still warned of heavy rainfall. WPC's Thursday outlook connects moisture associated with Polo's remnants to unusually moisture-rich air reaching the Midwest and Mid-Mississippi Valley. (NHC; WPC)
Other weather features are part of the setup too, including a slow-moving front and a larger storm system over the central United States. The practical issue is where heavy rain persists or repeats, not whether the original hurricane still has a name on a forecast map. This is a rainfall and runoff story, not a forecast of hurricane-force winds across the Plains. (WPC forecast discussion)
What to do before tonight's rain
If your location is still safe and you have time, prepare before the next round arrives. The National Weather Service's pre-flood guidance recommends identifying routes to higher ground, charging essential electronics, packing for family members and pets, checking sump pumps, and using protective materials only when there is sufficient time.
- Check your address, not just your state. Read the latest local forecast and official warning text. Our Flood Watch page displays National Weather Service alerts and lets you filter by state, but it is not a substitute for official local guidance or a life-safety alert system.
- Make the leaving decision easier. Put medications, identification, chargers, essential supplies and pet needs together now. Identify a safe destination and a route that does not depend on crossing a low-water road.
- Check likely entry points while conditions are dry. Look at door thresholds, garage openings and other low points. Move vulnerable belongings out of low areas if you can do so safely. Do not enter standing water to reach equipment or possessions.
- Prepare barriers only if time and conditions allow. Measure the opening you intend to protect and stage materials before water rises. Our sandbag calculator can help estimate quantities for a planned barrier; it cannot forecast your local flood depth or establish that a property is safe.
- Keep official alerts available overnight. Charge your phone and have a battery-powered radio available. With some of the forecast's heavier rain arriving after dark, finish reasonable preparations before bedtime rather than waiting to see water at the door.
For planned protection of vulnerable openings, StormBags provide a compact alternative to storing loose sand and filling bags. Activate them with fresh water and follow the product's deployment instructions. Barriers are property-protection tools, not a reason to remain in a dangerous area or delay an evacuation.
When preparation should stop
If water is rising, access is becoming unsafe, or officials direct you to leave, stop working on the property and move to safety. NWS advises avoiding floodwater and not waiting until it is too late to evacuate. A partially finished barrier is not worth losing your safe exit. (NWS: During a Flood)
Make that decision with everyone in the household before conditions deteriorate. Agree on who will gather the pets, where essential supplies are kept, and where you will meet if you are apart. If a preparation task would leave someone alone outside or make it harder to leave, skip it.
The next useful step is local, not complicated: check the latest warning information for your address, finish only what can be done safely, and have a way out. For help interpreting the language in those alerts, read our guide to flood watches, warnings and emergencies. Recheck official conditions before traveling, even if the rain at your own house has eased.
