Spring Flood Outlook…

It’s been since 2013 since the Lower 48 has seen greater snow cover on the 23rd of March.

Officially, 25.4% of the Lower 48 is currently snow covered, including crucial areas that feed downstream rivers in the north-central Plains and upper Midwest.

NOAA released their Spring Flood Outlook Friday. This shows major to moderate flooding expected on area rivers from the northern Plains south along the MS River. Even moderate to minor river flooding is anticipated across the east, including the Ohio Valley.

The full report can be found here.

As we move into April, a ridge is expected to back west and result in an active storm track from the west into the Mid West and Great Lakes. The end result will be a favorable pattern for above average precipitation. Factor that in with the above average late season snowpack currently in place across the exact same region, and the stage is set for moderate to significant river flooding through the remainder of the spring.



More specific to central Indiana, we also expect an active spring storm track- including precipitation that is around “average” from the March through May (meteorological spring) period. As warmth expands as we move into mid-April, expect an uptick in severe weather episodes further north during the 2nd half of April into May.

More On The Late March-Early April Pattern And Reviewing The NEW JMA Weeklies…

As we look ahead, a persistent western Canada/ Alaska ridge continues to show up on the medium to long range data. The downstream implications are for cooler than normal temperatures, overall, across the eastern and central portions of the country into early April.

Upper air pattern- Days 4-9
Surface temperature anomalies- Days 4-9
Upper air pattern- Days 9-14
Surface temperature anomalies- Days 9-14

Given the time of the year (and pattern), cool won’t rule the entire period. It’s just that the cold will “out do” the transient warmth in between storm systems over the next couple of weeks.

When we look at the teleconnections (combo of negative EPO and neutral to slightly positive PNA is ruling the day for now), they support the lingering chill into early-April.

However, as we turn the page from early-April to mid-April, the idea here is that an eastern ridge will begin to expand west with more “umph” and eventually lead to warmth overwhelming the pattern. We aren’t budging from the original idea of a warmer than normal April by month’s end. It sure appears as if the NEW JMA Weeklies are catching onto this idea.

Weeks 3-4 (mid April) forecast upper air pattern.

From a precipitation perspective, the majority of medium and long range model data does show a return of wetter times (relative to normal) as we move into April, including an active storm track. The beginning of this overall shift in the pattern back towards wetter than normal conditions will begin early next week.

We’ll recap our latest short-term thinking, including an update on the NEW European Weeklies that will arrive this evening later tonight in a video update.

In the meantime, make it a fantastic Thursday- and happy tip off to March Madness!

All-Access Video: Showers Arrive Later Today; Still Expecting A Beautiful Weekend And Looking Ahead To More Active Times…

A weak system will spread showers across central Indiana later today. We take a look at timing and amounts, along with spending time going over the long range pattern into…

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