Winter returns on March 8th. February and March have swapped places so let's pretend like this is the month of February and last month was March.
Here's what the National Weather Service has to say:
Short Term...(Today and tonight) Issued at 307 AM EST Thu Mar 2 2023 ...Heavy rain becoming more likely late tonight through Friday... Key Messages: - Flood watch issued for all of Central Indiana - Rain is expected to overspread the region late this evening, with pockets of moderate to at times heavy rainfall overnight through much of Friday. Some embedded thunderstorms may accompany the steady rain, with the main focus for thunder being along and south of a Terre Haute to Indy to Muncie line. - There is also a potential for hazardous wind conditions Friday, but there are some caveats that could hold the higher gusts aloft and not reach the surface. Details will be highlighted below in the discussion for Friday. This morning through Today... Broad anti-cyclonic surface ridging is drifting east across the Great Lakes region. This has allowed the cirrus shield to persist across the Southern Missouri Valley, stretching northeast over Central Indiana. Surface conditions remain benign, with a light northerly flow, and temps generally have radiated into the mid 40s. Expect for much of the day minimal changes to occur in the weather conditions, with the exception being wind direction. The pressure gradient will become oriented from the northeast to southwest, allowing winds to shift northeasterly but the lack of a robust gradient should allow speeds to generally be sub 10kt. Cirrus shield will likely persist through the afternoon hours. Given some solar shielding of the sun, and lack of a thermal ridge, temps will likely not see the diurnal surge from Wed and remain contained within the upper 40s to middle 50s. Tonight... Focus turns towards the developing shortwave, progged to arrive Friday across the region. Prior to the arrival the stage will be set with several ensemble members still pointing at lengthening vectors of the integrated water vapor transport, pointing from the the Central GOMEX northward towards the Ohio Valley. Current ensembles indicate the potency to be 3 to 4 sigma in strength, which coupled with the robust meridional flow in the 850-700mb layer would suggest that the potential for moderate/steady rain to at times heavy pockets appears favorable for much of Central Indiana. This has resulted in the need for a flood watch for the entire forecast area. Given the antecedent conditions of moist soils already in place, and the high confidence of rainfall in excess of 2 inches, this headline seemed prudent given the setup and expected conditions. Flood watch will continue until 6z Sat. Current timing has the shortwave beginning a northerly track from the Arklatex region around 6z Fri. Mid-lvl 500mb vort max is aligned with the surface features, and guidance continues to lift this feature north. Downstream the departing surface ridge will begin to slow, which should allow for further amplification to this synoptic system. This may briefly delay full saturation of the profile, but it appears to be only brief with strong isentropic ascent to parcels quickly moistening by 12Z Fri. Friday...There does appear to be some hints at a very slight negative tilt to the upper level features and the surface, which could shift the axis of higher rainfall values a touch northwest and bring a slight erosion to the moist layer into the southwest forecast area late Fri afternoon. Confidence remains high for heavy rainfall through much of the day Fri, but equally a concern for hazardous winds. Guidance has also continued to suggest some embedded thunderstorms with this setup Fri, but the emphasis on any organized severe elements appears to be more focused further south across Kentucky/Tennessee. But with mentioned negative tilt to the upper level support and this could also shift the convective concerns further north as well. Some caveats to seeing the higher winds materialize focus on the strong isentropic ascent of warm parcels creating a warm layer aloft. This could inhibit the potential for better mixing to the surface and resulting in winds remaining in the 30-35mph gust range for the area. Further south along the Ohio River appear to be more favorable where better mixing could easily occur and transport the 40 to 45 kt gusts to the surface. Friday night...Shortwave will continue to lift north late Fri evening, and bring a quick end to the precip shield as the deeper moisture peels quickly to the northeast and a dry layer arrives. A frontal boundary will then pass the region and bring a return to more seasonal air. && .Long Term...(Friday through Wednesday) Issued at 307 AM EST Thu Mar 2 2023 Weather impacts in the long term should be minimal. One minor precipitation event is expected late Monday into early Wednesday. Temperatures for most of the long term period will be above normal until a cooler pattern evolves the latter half of next week. Meteorological details and uncertainties are discussed below. Saturday: Cyclonic low level flow, residual low level moisture and ascent from relatively weak upstream shortwave trough would keep stratus through about midday or early afternoon. Neither of the shortwave troughs will be effective at dislodging higher latitude cold air, so the cool-down will be modest. Still about 10 degrees above climo. Sunday: The synoptic-scale pattern amplifies Sunday enough for some increase in temperatures, but the warm plume aloft holds southwest before the end of the diurnal mixing cycle so this will limit the warm-up somewhat. Monday: We`re a little more favorably positioned relative to deep ridging for a warm plume to advect over, and so we`re slightly higher with temperatures compared to a blended process to account for model deficiencies with mixing/PBL details (as we saw yesterday with temperatures near the 90th percentile of the ensemble distribution). Pacific moisture connection within westerlies, augmented by ascent from the approaching shortwave trough will ensure increasing cirrus, but deep moisture is mainly confined closer to the Ohio River, and deflected eastward as ascent moves through so only low probability of measurable precipitation late Monday and Monday night. Tuesday through Thursday: Post-frontal environment should be modestly cooler Tuesday, but continued veering of low level flow with broadening eastern trough should cause progressively cooler temperatures into the latter half of next week. Generally a dry period with deeper moisture relegated south, and only modest perturbations transient within the westerlies. Day 8-14: A colder pattern than recent days, but medium-range ensemble guidance is chaotic with position of synoptic features and therefore (1) magnitude of cold, and (2) potential for precipitation events.
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