textproduct: Wilmington

WHAT HAS CHANGED

No significant changes.

KEY MESSAGES

1) A deep low pressure system brings the chance for severe thunderstorms, isolated flooding, and gusty winds late this evening and Thursday. The most widespread severe storm risk will be tonight.

DISCUSSION

KEY MESSAGE 1)

Main story remains unchanged with severe thunderstorm threat for this evening into tonight. Broadly, a strong surface low (for mid June) will develop across the Upper Midwest and shift east across the Great Lakes tonight. Ahead of this low, a very strong southerly low level jet (60-70 knots) will advect moisture into the middle Ohio Valley this evening. This, combined with strong westerly flow aloft, will create long and curved hodographs into tonight. The main question remains how much instability will be present, especially across our northern counties where a weakening morning MCS may cause rain to persist from late this afternoon well into the evening.The kinematic parameter space will likely support all threats, including strong tornadoes (mainly in our western counties).

In addition, heavy rainfall and the possibility for isolated flash flooding remains a concern. PWATs near 2" and the potential for intense convective rates along a southward "sagging" line combine with terrain and urban sensitivities to lead to the main threat across our southern and southwestern counties. Gusty southerly winds this evening into the overnight (outside of storms) will shift to westerly on Thursday with gusts to 30 mph.

AVIATION /1Z WEDNESDAY THROUGH SUNDAY/

Weakening convective system will approach the northern terminals from DAY to CMH/LCK late this afternoon into the early evening. Have opted to keep visibility VFR due to the system's southerly track and current lack of lightning. Behind this, a strengthening surface low pressure system will approach late this evening into the overnight. The tightening pressure gradient will cause gusty southerly winds, becoming southwesterly to westerly behind the system on Thursday. Low level wind shear will also be prevalent due to a very strong low level jet aloft. However, the main impact of the low will be the potential for an intense line of storms impinging on the terminals from the 05Z to 09Z time frame. Will need to monitor convective wind gust potential as the storms develop and will include these in future TAF issuances.

OUTLOOK...Significant weather is not expected.

ILN WATCHES/WARNINGS/ADVISORIES

OH...None. KY...None. IN...None.