####018004677#### FXUS64 KMRX 111841 AFDMRX Area Forecast Discussion National Weather Service Morristown TN 241 PM EDT Sat May 11 2024 ...New SHORT TERM, LONG TERM... .SHORT TERM... (This evening through Sunday) Issued at 155 PM EDT Sat May 11 2024 Key Messages: 1. Isolated to scattered showers are expected late this afternoon into the evening hours. 2. Pleasant weather expected for the Mother's Day holiday. Discussion: In the upper levels, northwesterly flow is in place with a ridge building into the region tomorrow. At the surface, a cold front is currently over Central Kentucky, starting to move into Middle Tennessee. This front will move through the region this evening. With a fairly dry air mass at the surface, showers ahead of the front will be spotty with the best chance for a shower in SW Virginia and NE Tennessee in the late afternoon hours and into the evening. Thunder potential is low but a few strikes cannot be ruled out. Tonight, expect clearing skies after midnight allowing lows to get down into the 40s by morning. Some fog development will be possible mainly near bodies of water. Sunday will be dry with highs mainly in the 70s with high pressure over the Southeast. && .LONG TERM... (Sunday night through next Saturday) Issued at 155 PM EDT Sat May 11 2024 Key Message: An active start to the work week, with rain and thunderstorm chances through at least Wednesday. Another system looks likely at the end of the week. Discussion: Monday will bring about a change in the synoptic pattern as the ridging over the region is slowly overtaken by a slow moving low/trough moving out of the southern plains towards the Ohio Valley. We'll see increasing Gulf moisture ahead of the system with rain moving into the southern Valley in the morning hours, and spreading northward the rest of the day. Expect morning precipitation to most likely just be showers, but once we get into the afternoon/evening hours we should start to see some thunder thrown into the mix in some locations that are able to get a bit of sun breaking through the cloud deck. On Tuesday we should see greater coverage of precipitation and more thunderstorms as the upper level low looks to track right through the Ohio/Tennessee Valley, getting additional support from the in the right rear region of the upper level jet. Tuesday could see some strong storms, but the more likely threat will be from possible flooding with the additional storms bringing locally heavy downpours. Current forecast is showing generally around 0.5-1.5 inch rainfall totals for Monday into early Wednesday, however with the more isolated to scattered nature of the convection we can expect some places to see more than 1.5 inches. Combine this with the fact that river/stream levels may still be elevated from the rainfall earlier this week and we could see re-aggravation of flood prone areas. Am still in agreement with the WPC Marginal risk outlook for Tuesday/Wednesday in the southern Appalachian Region. We'll get a bit of a break during Wednesday evening as the slow moving system finally departs east of the Appalachian Mountains and we'll hopefully see mostly clear skies into Thursday ahead of the next system. That next system looks to be a much faster moving trough expected to zip through the eastern half of the United States Friday and/or Saturday. Still some disagreement in the deterministic models with the timing and northern/southern extent of this system, but at this time it looks likely that the end of the work week and start the weekend with another wet and stormy period. && .AVIATION... (18Z TAFS) Issued at 127 PM EDT Sat May 11 2024 VFR conditions are expected this TAF cycle with the possible exception of some fog forming near TRI in the early morning hours. Showers will be spotty late this afternoon into the evening hours but TRI has the best chance. Clouds will clear out by midnight or so making fog development possible mainly near bodies of water. && .PRELIMINARY POINT TEMPS/POPS... Chattanooga Airport, TN 54 81 57 73 / 0 0 0 50 Knoxville McGhee Tyson Airport, TN 50 76 53 76 / 20 0 0 30 Oak Ridge, TN 48 77 53 75 / 10 0 0 40 Tri Cities Airport, TN 46 73 48 76 / 20 0 0 20 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ SHORT TERM...McD AVIATION...McD ####018003869#### FXUS63 KSGF 111842 AFDSGF Area Forecast Discussion National Weather Service Springfield MO 142 PM CDT Sat May 11 2024 .KEY MESSAGES... - Dry and seasonable conditions will continue today and tonight. - Scattered shower and thunderstorm chances (10-40%) return Sunday afternoon and evening then become widespread late Sunday night into Monday. Continued chances (20-60%) linger into Tuesday, particularly east of Springfield. - Additional shower and storm chances (30-60%) will be possible late in the week as another system moves through the region. && .SHORT TERM /THROUGH TONIGHT/... Issued at 259 AM CDT Sat May 11 2024 An upper level trough is currently moving southeast into the Great Lakes region early this morning. The trough will continue to move to the southeast today as an upper level trough builds east into the Plains. An upper level northwest flow pattern will occur across the area today keeping dry conditions across the area. Surface high pressure will move east towards the area today with light northwesterly winds occurring this afternoon. Light and variable winds develop tonight as the area of surface high pressure moves across the region. Highs today will warm into the middle to upper 70s with lows in cooling into the upper 40s to middle 50s tonight into Sunday morning. && .LONG TERM /SUNDAY THROUGH FRIDAY/... Issued at 259 AM CDT Sat May 11 2024 The upper level ridge will move east over the region on Sunday. A warm front will lift northeast through the area and some weak uncapped elevated instability will develop across the area Sunday afternoon and evening. Some isolated to scattered showers and thunderstorms will be possible Sunday afternoon and evening but overall coverage should remain limited as a drier air mass in the mid levels will be in place. Therefore, many locations will remain dry through Sunday evening. The ensemble model members continue to indicate an upper level low moving across the central Plains on Sunday night into Monday morning and across the region Monday into Tuesday morning. As the upper level low moves east moisture and lift will increase across the region. As a result showers and thunderstorms will begin to increase in coverage across southeastern Kansas and western Missouri Sunday night and will spread across the entire area on Monday. As the low moves off to the east the coverage in shower and storms will decrease from west to east later Monday into Tuesday but some showers and storms will linger into Tuesday afternoon at times especially east of Highway 65. The better instability and severe risk are still expected to remain south of the region on Monday. The better moisture will also remain south of the region, and limit the overall widespread excessive rain risk across the area. Still some localized minor flooding may be possible on Monday given recent rains and the slow movement of this system. An upper level ridge will move east over the region on Wednesday and overall most locations should remain dry. The ensemble model members continue to differ late in the week with the track, structure, and timing of another upper level trough. Additional shower and storm chances will be possible Thursday into Friday but confidence on any one solutions and details such as timing, shear, instability, and moisture return still remain low at this time. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 124 PM CDT Sat May 11 2024 VFR conditions and light winds will continue through the TAF period. && .SGF WATCHES/WARNINGS/ADVISORIES... KS...None. MO...None. && $$ SHORT TERM...Wise LONG TERM...Wise AVIATION...Titus ####018003236#### FXUS62 KKEY 111844 AFDKEY Area Forecast Discussion National Weather Service Key West FL 244 PM EDT Sat May 11 2024 ...New DISCUSSION, MARINE, AVIATION... .DISCUSSION... Issued at 240 PM EDT Sat May 11 2024 GOES-16 visible satellite imagery certainly depicts a summertime pattern. A broken cumulus cloud line extends along the entire island chain, but has not been able to produce any shower activity this afternoon. Outside of this cloud line, skies are mostly sunny across the nearshore and offshore coastal waters. Temperatures are in the upper 80s at most island communities, with heat indices in the mid to upper 90s. A rather routine forecast for the next seven days expected. A frontal boundary draped over South Florida will continue to slowly sag southward this weekend before stalling and continue to weaken. The resulting collapsed flow will support a broken cloud line yet again tomorrow, but forecast soundings suggest scant boundary layer moisture will keep the Florida Key dry through the weekend. For next week, global ensemble guidance suggests a mid-level ridge over the Gulf of Mexico extending to the Florida Keys will be a bit stronger than initially anticipated in earlier forecast iterations. This suggests the Florida Keys should remain largely dry for next week. With that said, subtle moisture undulations will push through the Florida Keys coastal waters at times. Given this scenario, it seems prudent to nudge towards climatological measurable rain and thunder chances for the extended forecast for now (10-20%). The main story for next week will be the at times oppressive heat owed to the aforementioned ridge. Highs may approach the lower 90s by the end of next week. Combined with dew points in the upper 70s, heat indices will likely easily top 100F for several hours each day. Summer is here. && .MARINE... Issued at 240 PM EDT Sat May 11 2024 From synopsis, winds will continue to clock around the compass over the weekend, as this front approaches and dissipates in the vicinity of the Florida Keys on Sunday. Another high pressure area will slide over the western North Atlantic, resulting in gentle to moderate southeast to south breezes for much of next week. && .AVIATION... (18Z TAFS) Issued at 240 PM EDT Sat May 11 2024 VFR conditions will prevail at both terminals through tomorrow afternoon. West southwest surface winds will gradually veer to the northwest to north overnight and into tomorrow, with speeds remaining between 5 and 10 knots. && .CLIMATE... On this day in 1883, the daily record rainfall of 4.85" was recorded in Key West. Rainfall records date back to 1871. && .PRELIMINARY POINT TEMPS/POPS... Key West 89 79 89 79 / 0 0 0 10 Marathon 88 79 88 80 / 0 0 0 10 && .KEY WATCHES/WARNINGS/ADVISORIES... FL...None. GM...None. && $$ Public/Marine/Fire...BT Aviation/Nowcasts....NB Data Acquisition.....NB Visit us on the web at weather.gov/key Follow us on Facebook and Twitter at: www.facebook.com/nwskeywest www.twitter.com/nwskeywest