US Day 3-7 Hazards Outlook NWS Weather Prediction Center College Park MD 348 PM EDT Mon Oct 21 2019 Valid Thursday October 24 2019 - Monday October 28 2019 Hazards: - Heavy rain across portions of the Southeast, the Lower Mississippi Valley, the Southern Plains, and the Tennessee Valley, Thu-Fri, Oct 24-Oct 25. - Heavy rain across portions of the Lower Mississippi Valley, the Tennessee Valley, the Middle Mississippi Valley, the Southern Appalachians, the Southeast, and the Ohio Valley, Sat, Oct 26. - Flooding likely across portions of the Pacific Northwest and the Northern Great Basin. - Much below normal temperatures across portions of the western High Plains and the Northern/Central Rockies, Mon, Oct 28. - Enhanced wildfire risk across portions of southern California, Thu, Oct 24. - Heavy precipitation across portions of mainland Alaska, Sat-Mon, Oct 26-Oct 28. - Heavy rain across portions of mainland Alaska and the Aleutians, Fri, Oct 25. - Heavy snow across portions of the Alaska Panhandle and southeastern mainland Alaska, Thu, Oct 24. - High winds across portions of the Aleutians, Thu-Fri, Oct 24-Oct 25. - High significant wave heights for coastal portions of the northeast Gulf of Alaska and the Alaska Panhandle, Thu, Oct 24. Detailed Summary: A cold front will push through the Southern Plains on Thursday and slow as it sinks into the western Gulf Coast. An influx of moisture will interact with the front to aide in producing locally heavy rainfall over much of central/eastern Texas then spreading eastward across the Lower Mississippi Valley Friday/Saturday. A wave of low pressure may develop along the front out of the northwestern Gulf and move through Louisiana/Mississippi, enhancing the rainfall threat. This area of rainfall will move northeastward on Saturday into the Tennessee Valley as the system moves east-northeastward. By early next week, temperatures in the West will trend cooler as upper troughing and a surface cold front move southward and eastward through the Great Basin. The east-west extent of well below normal temperatures is in question due to the week-long lead time, but generally the area along and east of the Divide from Montana/Idaho southeastward through Wyoming is most favored for temperature anomalies of 10-20F below normal. Over southern California, an enhanced wildfire risk on Thursday was noted by the Storm Prediction Center coincident with gusty offshore winds. This may subside after the cold front passes by but may increase with the next cold front through the Great Basin this weekend. Confidence was not high enough to draw a hazard area yet for the Southwest next Sun/Mon. Over Alaska, an active period will continue with multiple hazards for the state. A lead system will exit the Panhandle on Thursday but not before producing some modest coastal rains and heavy mountain snow. Areas east of Anchorage from the Chugach to the St. Elias Mountains may see more than 1-2 ft of snow with Southwest flow slowly subsiding. Waves associated with the Gulf system may exceed 20ft offshore and approaching coastal locations. Once that system exits, a strong central Pacific system will move across the western or central Aleutians Fri/Sat with strong southerly flow and increasing rain for the island chain. The lead area of low pressure may fade before a trailing low may merge with the front which would only slowly move the heavy rain (and interior snow) threat eastward. By Sun/Mon, a deep moisture connection to the subtropics will help bring heavy rain/snow to western areas of Alaska and southern coastal areas of the Kenai peninsula with sustained southerly flow. Precipitation type may be changeable from south to north (changing from snow to rain) as warmer air pushes northward through the interior and western coastal areas this weekend. Fracasso