Update No. 3 (6:30 am on 17 April 2024)
Summary of changes:
Storm impact shifting to central Oh area;
Focus of weather production is 2 pm to 5 pm (dependent on how much sunshine we receive between now and then);
Risk for Clinton County is still SLIGHT (ranked 2 out of 5) with damaging winds as the main threat, with potential for large hail, and an isolated tornado or two (mostly in the central Ohio area).
SPC now showing a Day 2 (Thursday) potential for severe weather.
Spoiler alert ... forecast discussion posted at the end of this update.
NWS OnePager issued 2:50 am on 17 April:
- - Wednesday (17 April 2024) - -
Storm Prediction Center (SPC) Day 1 Severe Weather (Wednesday):
SPC Day 1 Damaging Wind Risk (15% for Clinton County):
SPC Day 1 Tornado Risk (2% for Clinton County):
SPC Day 1 (Wednesday) Hail Risk (15% for Clinton County):
- - THURSDAY (18 April 2024) - -
SPC Day 2 (Thursday) potential for severe weather:
SPC Day 2 (Thursday) Tornado Risk (2% for Clinton County):
SPC Day 2 (Thursday) Hail risk (15% for Northern Clinton County and 5% for the southern portion):
SPC Day 2 (Thursday) Wind Outlook (5% risk for damaging winds for Clinton County):
Forecast Discussion:
FXUS61 KILN 171052
AFDILN
AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
652 AM EDT Wed Apr 17 2024
.SYNOPSIS...
Showers and a few thunderstorms will be found over the region today ahead of a cold front crossing in the late day and early evening. Zonal westerly flow will be found behind the front until a surface low tracks through northern Ohio overnight Thursday, with a trailing cold front affecting the entire region. Building high pressure behind this second front will keep a cool pattern in the Ohio Valley through the weekend.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
There is a strong push from the models to limit any showers over the region to the northern CWA, where thunder will be at a peak from 19-23Z. Strong winds 15-25 mph with gusts to 30-35 mph will make for a breezy day. Day 1 outlook did not agree with the chance of precipitation as noted by surrounding forecast offices including ILN. Our forecast this morning looks overdone when compared to surrounding offices, but it felt too hasty for our area to be cut that much that early.
Severe threat appears to be limited to CWA along and north of the I-70 corridor, probably a little more north than along. As per usual lately, model agreement is not so easy to come by. A few note a strong decrease in this afternoon's dewpoints, into the mid and lower 50s which would lead to little activity if realized. The negatively tilting trough crossing through northwest Ohio has been gaining some speed when compared to prior models. This suggests a very narrow corridor where dynamics /could/ come in play with an equally narrow corridor of moderate instability. This instability is primarily aloft and any lower based storms would need to punch through a fairly strong cap. Likewise, elevated storms that may develop will have a difficult time bringing the bulk of their energy to the surface, and the bulk of the energy available looks to be modest at best.
All this being said, a slight chance of severe winds near 60 mph could accompany the strongest storms for a brief window of time this afternoon over the northern third of the CWA. Expect the trend will be to reduce even more the threat and footprint of storms as new models come in this morning.
Highs today will be in the 70s with breezy conditions.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 PM THURSDAY/...
A cold front will have crossed most of the CWA by this time, but may still be located east of the Scioto River. Winds will have died down to a more manageable 8-12 mph overnight, more like 10-15 over the northern half. A surface ridge of high pressure will work into western CWA by daybreak. This will cut winds even more to the 5-10 mph category that should persist through the day as the high crosses to the east.
With clearing sky cover, overnight lows will drop from the upper 40s in the northwest, low 50s for most of the CWA, and maybe only the mid 50s over parts of northern Kentucky and the lower Scioto Valley.
Some increasing high clouds on Thursday will be found in the latter half of the day, particularly in the northwest. A lighter wind and abundant sunshine for most of the area will see highs reach the mid and upper 70s, some lower 70s in west central Ohio.
[END]
- - - - - - - - - - - - - - -
Update No. 2 (8 am on 16 April 2024)
Summary of changes:
Tuesday (16 April) - Potential for severe weather with timing between 2 pm to 8 pm. Risk rating for Clinton County is 1 out of 5 (MARGINAL).
Gusty winds that could impact trees and yard ornaments, and potentially result in some local power outages.
Hail is possible for Tuesday.
Wednesday (17 April) - Potential for severe weather with timing between 2 pm to 8 pm. Risk rating for Clinton County is 2 out of 5 (SLIGHT).
Gusty winds, large hail, and a possible tornado can not be ruled out.
National Weather Service OnePager issued 16 April at 2:54 am:
-- TUESDAY --
Storm Prediction Center (SPC) Day 1 Outlook (Tuesday):
SPC Day 1 Wind Outlook (Tuesday):
-- WEDNESDAY --
SPC Day 2 Outlook (Wednesday):
SPC Day 2 Wind Outlook (Wednesday):
SPC Day 2 (Wednesday) Hail Outlook:
SPC Day 2 (Wednesday) Tornado Outlook (2%):
[END]
- - - - - - - - - - - - - - -
Initial Posting: 15 April 2024
This is your initial Prepare Now Message (PNM) for potential severe weather for this Wednesday, 15 April 2024.
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK 0224 AM CDT Mon Apr 15 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE LOWER OH VALLEY TO MID-SOUTH... ...SUMMARY... Scattered severe thunderstorms are possible on Wednesday afternoon to early evening across parts of the Lower to Central Ohio Valley into the Mid-South. ...Parts of the Midwest to Mid-South... Occluding surface cyclone in the northeast IA vicinity on Wednesday morning will further dampen as it tracks towards Lower MI. Despite weakening tropospheric flow fields, favorable low to deep-layer shear profiles should persist into early evening. The northeast lobe of the warm-moist sector emanating from the western Gulf should spread across at least the Lower OH Valley. While some low-level warm theta-e advection-driven convection may be ongoing at 12Z Wednesday, overall signals have been for less convection impacting the buoyancy plume compared to prior forecasts. As such, potential for greater daytime destabilization is apparent, with a moderate MLCAPE field from 1000-2000 J/kg likely. Most guidance suggests early afternoon convective initiation will occur along the cold front trailing south-southwest from the occluding cyclone. A mix of all severe hazards appears possible with both supercells and multicell clusters. Greatest convective concentration is expected near/north of the Lower to Central Ohio Valley. The buoyancy plume should be more confined within this corridor and eventually pinch off as overturning occurs. With further diminishing of flow fields into the evening, the severe threat will wane after dusk. ..Grams.. 04/15/2024
Hazardous Weather Outlook
Hazardous Weather Outlook
National Weather Service Wilmington OH
518 AM EDT Mon Apr 15 2024
INZ050-058-059-066-073-074-OHZ026-034-035-042>046-051>056-060>065-
070>074-077-080-082-160930-
Wayne-Fayette-Union-Franklin-Ripley-Dearborn-Hardin-Mercer-Auglaize-
Darke-Shelby-Logan-Delaware-Miami-Champaign-Clark-Madison-Licking-
Preble-Montgomery-Greene-Pickaway-Fairfield-Butler-Warren-Clinton-
Ross-Hocking-Hamilton-Highland-Pike-
518 AM EDT Mon Apr 15 2024
This Hazardous Weather Outlook is for east central Indiana,
southeast Indiana, central Ohio, south central Ohio, southwest Ohio
and west central Ohio.
.DAY ONE...Today and tonight.
There is a low probability for widespread hazardous weather.
.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.
A few strong to severe storms will be possible Wednesday afternoon
and evening. Large hail and damaging winds are the primary threats.
.SPOTTER INFORMATION STATEMENT...
Spotter activation may be needed Wednesday.[END]