Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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526 FXUS63 KIWX 281731 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 131 PM EDT Tue May 28 2024 .KEY MESSAGES... - Cool conditions with periodic showers and a few afternoon thunderstorms will continue through Wednesday. - Severe weather is not expected but a few storms may produce small hail and gusty winds during the late afternoon and evening today. The best chances for strong storms will be west of Highway 31. - Dry weather is expected Thursday and Friday but more rain returns early Saturday and into next week. && .DISCUSSION... Issued at 303 AM EDT Tue May 28 2024 Large negative height anomaly remains over the Great Lakes and eastern Canada through the next two days. Multiple vorticity maxima will rotate through the area during this time, leading to a continuation of relatively cool and cloudy conditions with periodic showers. One such vort max (currently a fairly potent one as seen on latest water vapor imagery) will swing through our area during the early morning and shear out a bit. This will support expanding clouds and showers (a process already occurring at press time) though unfavorable (stable) diurnal timing and overall modest forcing will keep showers scattered. There is then likely to be a lull in shower coverage around midday with a brief period of shortwave ridging in between troughs. This will be our best chance for more widespread sun but suspect at least some clouds to linger. This break will be very brief as another vort max approaches during the late afternoon/evening with increasing shower coverage once again. This will probably be our most widespread round with favorable diurnal timing and good midlevel CVA. A few thunderstorms are possible but instability appears meager. Shear is also very limited in our area and any storms that do develop have a very low chance of becoming severe. However, steep midlevel lapse rates and cold temps aloft yield some low potential for small hail and perhaps some isolated gusty winds. The best chances will be in our far west as reflected in the latest SWODY1. Highs today will be similar to yesterday though a bit warmer in our NE half. Anticipate highs to top out around 70F to low 70s. Moist, cyclonic flow continues overnight into Wed and will maintain chances for SCT showers with perhaps an isolated afternoon storm. Winds back to a more northerly direction on Wed and this will keep highs in the mid/upper 60s. Dry air advection and subsidence build across the area Wed night but models now show yet another trough swinging through the lower Great Lakes on Thu. Will hold Thu dry for now given strong negative theta-e advection and eastward displacement of best forcing but a widely isolated afternoon shower is not impossible. More sun is anticipated and this will add a few degrees to the highs despite continued northerly flow. Sharp midlevel ridge finally moves into our region Thu night/Fri. However highly amplified and progressive mid/upper level pattern will yield another trough passage Fri night/Sat. Midlevel CVA and low level moisture advection will support numerous showers but forcing weakens with time and instability appears limited especially given very poor diurnal timing. A brief break late Sat into Sun but more rain chances arrive late Sun into Mon as active pattern continues. Highs slowly climb back to near/slightly above seasonal averages through the period. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 125 PM EDT Tue May 28 2024 Upper level disturbance dropping through Wisconsin this afternoon with an area of showers and a few storms. Clearing skies have allowed steepening low level lapse rates and an increase in cu both here and upstream ahead of the wave. Models vary on start of chances for showers/storms, but seem to focus the greatest coverage (and chances for thunder) maybe as early as 23Z at KSBN but more likely in the 1-4Z period. KFWA more questionable with loss of heating and narrow window for thunder potential. Have made some adjustments with tempo MVFR groups for cig/vsby as well as thunder in most favored period. Can`t rule out some locally gusty winds or small hail, mainly at KSBN, but not covered in TAFs. Showers and MVFR cigs should persist overnight with the potential for a drop to IFR mainly at KSBN or during showers. While the showers should move away during Wed morning, flight conditions may be slow to improve so MVFR conditions maintained through the end of the period. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...AGD AVIATION...Fisher