The National Weather Service has expanded the Flash Flood Watch to encompass more of the viewing area. This is in effect until 8p Tuesday.
No doubt about it, today will be very wet across the entire region, including periods of heavy rain- especially across the western half of the state.
Tropical moisture will continue to stream into the state tonight into Tuesday. In fact, most intense rains will likely set up tonight and may feature “banding” signatures that would train over the same areas. Within these intense rain bands, prolific rainfall rates can be expected, enhancing the flash flood risk. Latest short-term model data shows this threat, and would place a premium focus on areas generally west of US-31. We’ll have to keep a close eye on things.
Plenty of “juice” is available to tap into across western sections tonight. Precipitable water values (PWATs) of 2″-2.5″ will be more than enough to fuel torrential rainfall.
Eventually (mid and late week), we’ll dry things out and a significant cool down is still in store developing this weekend into early next week. Lows will fall deep into the 50s with highs only in the 70s. Talk about an early taste of fall…
Despite lackluster model output from our American suite (latest NAM and SREF data, for instance, paints rainfall totals under 1″ across most central IN neighborhoods), the European remains consistent on the evolution of things from this weekend into the middle of next week. We’ll lean more towards it’s solution at this juncture. Simply put, when you have a stalled frontal boundary entraining tropical moisture, expect problems. Precipitable water values will approach and even exceed 2″ at times this weekend. Dew points will remain in the upper 60s to lower 70s along and south of the boundary. Where the boundary stalls will be key in determining the heaviest rain totals and resulting flood problems that will ensue. For now, here’s the best idea we have in regards to local 4″+ totals between this weekend and next Wednesday.
It should also be pointed out that we’re not looking at all day rains Saturday through Wednesday, but instead “waves” of moisture throughout the period. Areas of locally heavy rain will be with us, but we’ll also see dry periods in between. Thankfully, as we move into the latter portions of next week, drier times should return.