Area Forecast Discussion
Issued by NWS Louisville, KY
Issued by NWS Louisville, KY
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283 FXUS63 KLMK 101836 AFDLMK Area Forecast Discussion National Weather Service Louisville KY 236 PM EDT Mon Jun 10 2024 .KEY MESSAGES... * Below normal temperatures and humidity through Tuesday. * A warming trend with hot and dry conditions likely late this week into next weekend. && .SHORT TERM /THROUGH TUESDAY/... Issued at 232 PM EDT Mon Jun 10 2024 Unseasonably mild and dry air continues to filter into the Ohio Valley this afternoon as a reinforcing cold front has just dropped south of the Ohio River. No precipitation associated with the front, as the main sensible weather impacts are an extensive strato-cu deck and a modest NNW wind surge with gusts around 20 to occasionally 25 mph. Expect the fall-like conditions to persist through mid-evening as the boundary layer will be a bit slower to decouple under cold advection. We will still have clear skies and light winds by midnight, but the dry air mass will limit overnight fog formation mainly to river valleys and other low-lying areas in south-central Kentucky. Another cool day on Tuesday, with a slight rise in low-level thicknesses offset by a less deeply mixed boundary layer. Afternoon highs close to persistence across southern Kentucky, perhaps a couple degrees warmer with more sunshine in southern Indiana and north central Kentucky. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... Issued at 232 PM EDT Mon Jun 10 2024 Tuesday Night - Thursday Night... A mostly weak, zonal pattern will be over the Ohio Valley at the beginning of the long term period. Dry air will continue into the late week, keeping dew points and PWATs lower than normal for mid- June. With a gradually building ridge over most of the US, temperatures will increase through the week. Starting the week off, we saw 1000-850mb thicknesses in the upper 1300dm and temperatures in the low-mid 70s. By the end of this week, we will see thicknesses near 1420dm and temperatures in the upper 80s and 90 in some areas. Friday and Friday Night... A shortwave trough will ride along the periphery of the building ridge and just brush the region. This system will send a cold front through the Ohio Valley on Friday. While the front will lead to increased lift and there will be some additional moisture out ahead of this front, not much is expected to materialize. Could see additional cloud coverage and about 10-20% PoPs. Saturday - Sunday... Ridging over the central CONUS will continue to build and shift to the east. This will allow for temperatures to continue to rise. As high pressure is over the region on Saturday, conditions will still remain on the dry side with dew points in the low-mid 60s. By Saturday night, high pressure is expected to shift to the east bringing returned (and dreaded) moisture into the region. Sunday, dew points are progged to be in the upper 60s and low 70s. Temperatures will likely be in the 90s at this point, and result in hot and muggy conditions. Forecast Confidence... Guidance has a large spread in regards to temperatures this week, with the ECMWF taking the high side and weighting the NBM higher. With a large amount of rainfall within the last few weeks, the region is quite green, and therefore, would take a while for evapotranspiration to then result in baking. Have decided to go with lower guidance for the forecast given green conditions. In the later part of the week, there is more confidence in higher temperatures. && .AVIATION /18Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 126 PM EDT Mon Jun 10 2024 VFR expected through the valid TAF period. Look for NNW winds gusting just shy of 20 kt in the cold advection regime this afternoon, along with strato-cu ceilings around 5k feet. Will keep it scattered at BWG and RGA where there is less cold pool influence. Winds will lay down gradually this evening, so we`ll keep a window of light NW winds and scattering/mid-level clouds through mid- evening before the boundary layer decouples. Will be light/variable with clear skies by midnight. Not expecting any fog in the terminals overnight with a very dry boundary layer, but there could be some valley fog east of BWG. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...None. IN...None. && $$ SHORT TERM...RAS LONG TERM...SRM AVIATION...RAS