658 FXUS21 KWNC 301852 PMDTHR US Hazards Outlook NWS Climate Prediction Center College Park MD 300 PM EDT September 30 2026 SYNOPSIS: A stationary front is predicted to stretch across or near the Gulf Coast, Florida, and the coastal Southeast during week-2 bringing increased chances of a prolonged period of episodic heavy rainfall to the Gulf Coast, Florida, and Southeast, including the coastal Carolinas. The greatest chances for this hazard is anticipated for northern and central Florida during mid week-2. A series of low pressure systems tracking from the Bering Sea and Aleutians to the Gulf of Alaska, further enhanced by remnants of tropical disturbances in the East Pacific, may impact southern portions of Alaska. The greatest concern would be gusty winds extending from coastal portions of southwestern, south-central, and southeastern Alaska, the Alaska Peninsula, and Aleutians. The highest chances for high winds are anticipated for coastal portions of south-central and southeastern Alaska mid week-2. These storms may also support heavy precipitation across parts of south-central and southeastern Alaska. HAZARDS Moderate risk of heavy precipitation for northern and central Florida, Thu-Sat, Oct 8-10. Slight risk of episodic heavy precipitation for Florida and coastal portions of the Gulf Coast and Southeast including the coastal Carolinas, Thu-Wed, Oct 8-14. Slight risk of high winds for coastal portions of the Gulf Coast, Thu-Wed, Oct 8-14. Moderate risk of high winds for coastal portions of south-central and southeastern Alaska, Sat-Mon, Oct 10-12. Slight risk of high winds across coastal portions of southwestern, south-central and southeastern Alaska, the Alaska Peninsula, and Aleutians, Thu-Wed, Oct 8-14. Slight risk of heavy precipitation for parts of south-central and southeastern Alaska, Thu-Wed, Oct 8-14. DETAILED SUMMARY FOR SATURDAY OCTOBER 03 - WEDNESDAY OCTOBER 07: https://www.wpc.ncep.noaa.gov/threats/threats.php FOR THURSDAY OCTOBER 08 - WEDNESDAY OCTOBER 14: The GEFS and ECENS continue to be in good agreement, indicating amplifying 500-hPa ridging (troughing) over western (eastern) North America during early October. A stationary front is anticipated to stretch from the Gulf Coast to potentially near or along the coastal Southeast south of the mid-level troughing over the East. This pattern supports a prolonged period of a slight risk (20-40% chance) of episodic heavy rainfall for parts of Florida and coastal portions of the Gulf Coast and Southeast including the coastal Carolinas throughout week-2. The GEFS and ECENS Probabilistic Extremes Tools (PETs) are in good agreement indicating at least a 20% chance of 3-day precipitation totals exceeding the 85th percentile and one inch across the designated hazard area. A moderate risk (40-60% chance) of heavy precipitation is designated for northern and central Florida, Oct 10-12, where the ECENS PET has increased coverage of at least a 40% chance of exceeding accumulated totals of 1 to 1.5 inches in 3-days, further supported by uncalibrated guidance. Furthermore, multiple models are indicating a potential, particularly at the end of week-2, for tropical disturbances tracking towards the Gulf from near Baja California and Bay of Campeche that would enhance onshore flow, further enhancing heavy rain. Additionally this pattern with surface lows near or along the Gulf Coast may also bring enhanced wind speeds to the region, supporting a slight risk of episodic high winds or the Gulf Coast. Multiple PETs indicate at least a 20% chance of wind speeds exceeding the 85th percentile and 25 mph further supported by ensembles indicating a 20 to 30% chance of wind gusts exceeding 34 knots (about 39 mph). Anticipated heavy rainfall and strong onshore flow, combined with expected enhanced rainfall totals from week-1, could lead to some areas experiencing flash flooding across the Gulf Coast. A highly amplified 500-hPa trough over the northeast Pacific is likely to promote a series of low pressure systems that track from the Bering Sea and Alaska Peninsula eastward to the Gulf of Alaska. The greatest concern regarding impacts would be for high winds, as depending on the track and evolution of the remnants of tropical disturbances in the East Pacific could lead to increased risk of high winds for southern Alaska. A moderate risk (40-60% chance) of high winds is designated for coastal portions of south-central and southeastern Alaska, Oct 10-12, based on where the ECENS PET of wind speeds exceeding the 85th percentile and 40 mph, model guidance of increased probabilities of 10m wind gusts exceeding 50 knots (about 57 mph), and good day to day model consistency regarding the pattern. A broader area of slight risk of high winds is posted for coastal portions of southwestern, south-central and southeastern Alaska, the Alaska Peninsula, and Aleutians for the entirety of week-2, where the GEFS and ECENS PETs indicate at least a 20% chance of wind speeds exceeding the 85th percentile further supported by uncalibrated guidance indicating elevated probabilities of wind gusts exceeding 50 knots. Based on the enhanced onshore flow associated with these low pressure systems, and support from the ECENS and GEFS PETs (20% chance of 3-day precipitation amounts > 85th percentile and 2-3 inches), a slight risk of episodic heavy precipitation is maintained from the Kenai Peninsula to southeastern Alaska throughout week-2. Recent deterministic models indicate the potential for daily totals exceeding 2-3 inches. Anticipated above-normal temperatures and dry conditions across the West may enhance wildfire risk, especially across the Cascades eastward to the Northern Rockies. Some of these areas are already experiencing active wildfires. In the Central and Eastern Pacific, the tropics remain very active with Hurricane Rachel, Tropical Storm Nolo, Tropical Depression 19E, and an area of low pressure south of Mexico with a 50% chance for Tropical Cyclone formation in the next week (as of 2:45pm EDT). Tropical Depression 19E is predicted to move generally eastward away from the Hawaiian Islands. This is good news for the residents of Hawaii that have already experienced a memorable hurricane season this year. It remains to be seen whether or not the evolution of Hurricane Rachel results in significant precipitation into the American Southwest in early October. FORECASTER: Melissa Ou $$