Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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853 FXUS63 KIND 121702 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 102 PM EDT Sun May 12 2024 .KEY MESSAGES... - Showers and storms expected Monday-Tuesday with 1-2 inches of rain - Near normal temperatures through the week && .FORECAST UPDATE... Issued at 948 AM EDT Sun May 12 2024 Forecast is in great shape this morning. Skies were mostly clear with only a few cirrus and some thin smoke from Canadian wildfires. Some additional cirrus will move in later today but sunshine will remain plentiful. Temperatures look good, so only minor tweaks to hourly forecasts were made based on latest observations. && .SHORT TERM (Today and Tonight)... Issued at 210 AM EDT Sun May 12 2024 Clear skies were present across much of the Ohio Valley early this morning...with just a small area of mid clouds passing through northeast parts of the forecast area currently. This has enabled a much better opportunity for widespread Aurora viewing across the area as the ongoing solar storm continues. 06Z temperatures ranged largely from the upper 40s to the upper 50s. An upper low over the eastern Great Lakes early this morning will move away from the area today...with ridging aloft settling over the Ohio Valley and joining the surface high already present. With low level flow transitioning to southwesterly and warm advection commencing...expect a wonderful finish to the weekend with warm and dry weather for central Indiana. After a cool start this morning as temperatures slide back into the upper 40s and lower 50s...temps will rise quickly with sunny skies and light winds. Winds will increase to closer to 10mph this afternoon as the center of the surface ridge settles to the southeast and return flow develops. Model soundings show another afternoon with deep mixing present up to nearly 9-10kft during peak heating which will also aid in increasing winds a bit. Some cirrus will drift into the region as the day progresses but the overall state of the sky will be for abundant sun into the early evening. A cutoff upper level low will eject out of the Rockies later today and progress into the central Plains by daybreak Monday. The approach of this feature will lead to a subtle increase in mid and high level clouds tonight but the combined tandem of ridging at the surface and aloft will keep plenty of dry air and subsidence across the region. Temps...the deep mixing present below 10kft will maintain lower dewpoints through the afternoon and should enable temperatures to outperform current guidance by a degree or two. Nudged afternoon highs up into the upper 70s and lower 80s for much of the forecast area. Lows tonight will remain in the mid and upper 50s aided by southerly winds at 5-10mph for much of the night. && .LONG TERM (Monday through Saturday)... Issued at 210 AM EDT Sun May 12 2024 Monday and Tuesday Southerly flow will become more robust Monday as a low pressure system exits the Rockies and begins to intensify as it tracks from Kansas into the Ohio Valley. Models have a pretty good handle on both the timing and strength of this low pressure system which helps create a high confidence forecast in a period of moderate to briefly heavy rain Monday evening through the overnight hours with rain amounts around 1-1.5 inches with the heaviest rain falling during the daytime hours on Tuesday. A deformation axis of heavier rain looks to set up on the northwest side of the low but this axis looks to remain northwest of the forecast area with areas near Lafayette on the far periphery of this area of enhanced precipitation. There will be additional precipitation Tuesday night on the backend of the system, but expect that coverage will gradually lessen after midnight going into Wednesday as the better forcing pushes into the East Coast. Wednesday Through Saturday Conditions look much quieter going into the middle of the week as high pressure builds in the aftermath of the early week system. Temperatures will remain near normal with little flow at the surface and aloft to advect warmer air into the area. Another upper level low is expected to take a similar track to the system earlier in the week Thursday night into Friday with another round of sub-severe showers and thunderstorms. The exact track with this system remains much more uncertain with model spread on the axis of heavier rain varying from central Indiana to as far south as Tennessee. There are some ensemble members that keep precipitation as late as Saturday, but those look to be the outlier with the vast majority allowing for a dry forecast for the weekend. && .AVIATION (18Z TAF Issuance)... Issued at 101 PM EDT Sun May 12 2024 Impacts: - No impacts through the forecast period Discussion: Some high clouds will move in this afternoon along with perhaps a few cumulus or mid level clouds. High then mid level clouds will increase tonight into Monday morning, with lower clouds waiting until after 18Z Monday to arrive. Isolated showers may get near the western sites late tonight or Monday morning, but confidence and expected coverage are too low to mention. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...50 SHORT TERM...Ryan LONG TERM...White AVIATION...50