TROUBLE AHEAD, TROPICAL DEPRESSION AIMS FOR IOWA...

June 7, 2020

A rare tropical depression is expected to make a direct hit on eastern Iowa Tuesday. According to the National Hurricane Center's tropical low track database dating back to 1886, there's only been two system that have actually tracked through Iowa. That certainly speaks to how unusual it is to have a post-tropical circulation track this far west, particularly since hurricane season doesn't kick into high gear for another 2-3 months! The last depression to do it was the remnants of Isaac in 2012.

 

This is the official forecast track from the National Hurricane Center.

The EURO EPS ensembles show this for a track. 

The EURO and GFS operational are further west cutting through EC Iowa into SW Wisconsin. The EURO has the low deepening over Muscatine, Iowa around 5:00 pm

 By 10:00 pm the circulation center has passed just west of Dubuque, Iowa into SW Wisconsin.

The pressure which dips to 982 mb is at least 4 standard deviations below June level intensity.

The strongest winds are likely going to be just east of the center. The EURO shows this for 10 meter wind gusts late Tuesday and Tuesday night. It's very likely that much of my area sees gusts to 40 with some 50-60 mph gusts, especially east of the Mississippi.

Adding to the complexity of the system will be the phasing of the tropical energy with a strong trough approaching from the west. That actually develops a secondary circulation and a fujiwhara effect.where the two votices orbit one another. This is a really fascinating scenario, one like I've never seen before with the inclusion of the tropical energy!

 

The precipitation is going to be heaviest west of the circulation position where 2-4" totals should be common. Some 5+ amounts are possible where mesoscale forcing is enhanced. Fortunately the system is moving at a pretty good clip or this could be a devastating flood threat. 

 

As it is, water vapor is shown on the EURO at 3.00" in several of my western counties.

 That's 2.5 to 3 times the normal levels in early June.

Here's the rainfall the latest EURO depicts.

The GFS shows this

 The WPC indicates this for an excessive rainfall threat Tuesday.

The system is set to arrive Tuesday with conditions at their worst during the afternoon and evening. Gusty winds and showers are likely to continue in may areas behind the storm on Wednesday.

 

Once again, this has the potential tolbe a high impact storm system for June. I fully expect flash flood as well as flood watches will be issued for much of eastern Iowa if trends continue to hold. If you are in the central Midwest be advised an extremely rare storm for this time of year is on the way with significant wind and rain. Roll weather...TS

 

Share on Facebook
Share on Twitter
Please reload

ARCHIVED POSTS
Please reload

RECENT POSTS
Please reload

© 2019 Terry Swails