Expires:No;;140759 FXUS64 KMEG 040504 AFDMEG Area Forecast Discussion National Weather Service Memphis TN 1104 PM CST Tue Dec 3 2024 ...New AVIATION... .SYNOPSIS... Issued at 228 PM CST Tue Dec 3 2024 Temperatures won't be quite as cold tonight, but low temperatures will still average 8 to 12 degrees below normal. Under increasing cloudiness, highs across the Midsouth will range from the lower to mid 50s Wednesday afternoon. A few light rain showers are expected south of Interstate 40 Wednesday afternoon. An Arctic cold front will pass through the Midsouth Wednesday night. The coldest air will lag behind the front a bit. For the Midsouth, our coldest temperatures are expected Friday morning, with lows ranging from the mid teens over northwest Mississippi to the mid 20s over northwest Tennessee. Mild and rainy conditions will settle in to the Midsouth late next weekend into early next week. && .DISCUSSION... (This evening through next Monday) Issued at 228 PM CST Tue Dec 3 2024 We're about five days out from an upper level pattern change across North America. The persistent longwave trough over the eastern U.S. and southeast Canada will lift out over the Atlantic by Sunday, allowing a progressive split flow upper level pattern to develop over the lower 48 states. In the interim, northwest flow will persist over the Midsouth. Another strong Arctic cold front will pass through Wednesday night. At that time, the core of Arctic air, a 1041mb pressure ridge, will be centered over the Dakotas. This high will settle into the Midsouth by late Friday afternoon. Though Friday morning will likely bring the coldest temperatures of the week, Thursday morning's apparent temperatures (wind chills) will be equally low to Friday's due to gusty winds immediately behind the Arctic front. By Saturday morning, southerly low level flow will commence behind the departing Arctic high pressure. Earlier model runs from a few days ago were depicting a potential freezing rain scenario Saturday morning, with southern branch moisture overspreading modified Arctic air near the surface. However, guidance has come into better consensus in developing an upstream ridge over east TX during this period. Midlevel moisture and QPF will be mainly confined to the diffluent flow west of the ridge axis over TX. Eventually, the ridge will deamplify and translate east, with rain edging into eastern AR Saturday night. By such time, thermal profiles will favor rain. In response to steep northern branch height falls over the Pacific Northwest, a southern branch cutoff upper low over northwest Mexico will eject into the southern plains on Sunday. A plume of moisture will develop through the lower and middle MS River Valley in advance of this feature. PWAT values will range from 1.4 to 1.8 inches by Monday morning across the Midsouth, nearing the 99th percentile of climatology. A Pacific cold front will bring cooler temperatures early next week. There is some question as to where this front may stall, which will impact rain chances toward the middle of next week. PWB && .AVIATION... (06Z TAFS) Issued at 1104 PM CST Tue Dec 3 2024 VFR conditions continue through most of the TAF period. Current light winds will become southwesterly and gusty by mid morning, with 20 to 25 kts gusts thereafter. Winds will fall back below 10 kts after 02Z, becoming west/northwest near the end of the current TAF period. Frontal boundary will bring low cigs to north MS and the potential for some -SHRA after 00Z. Low cigs could approach MEM for a few hours, mainly between 02Z and 05Z. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$ PUBLIC FORECAST...PWB AVIATION...CMA