The Storm Prediction Center (SPC) has significantly expanded the “slight risk” area to include a large portions of the state.
While a fresh batch of heavy rain will move into central Indiana later this morning (another 1″ to 2″ is a good bet for most communities), the focus shifts to a window where severe thunderstorms will be possible during the early to mid afternoon.
A warm front will lift north through central IN late morning and this will allow relatively warm and moist air to briefly surge as far north as a Logansport to Fort Wayne line.
Note dew points will spike to 60 to 63 degrees over much of central and eastern IN this afternoon.
It’s during the 1p to 5p window when we’re most concerned for the chance of a few severe thunderstorms ahead of the cold front. Damaging winds are of greatest concern, but anytime you have a warm front hanging around central Indiana with these kinds of setups, the potential of a tornado is in the back of your mind. I don’t foresee this being a major tornado outbreak whatsoever, but parameters do suggest the chance of a quick spin-up tornado is present, as well during this timeframe.
The cold front will crash into Indianapolis between 4p and 5p and you’ll certainly know it.
Strong and gusty northwest winds will blow sharply cold air into the region this evening and tonight. In fact, highs in the lower to middle 60s this afternoon will be into the 20s before midnight. Lows Friday morning will fall into the 10s and highs Friday will only top out in the lower 20s with wind chill values in the single digits most of the day.
After a dry open to the weekend, we continue to monitor the potential of a light wintry event Sunday into early Monday. This doesn’t appear to be a big deal, but the chance is there for an inch or two of snow for portions of the central and northern Ohio Valley during this timeframe.
Additional challenges await early and mid next week, but we’ll save those for updates later this afternoon or evening.
JMA Weeklies
The updated JMA Weeklies are in and in short suggest the southeast ridge continues to put up a fight over the next couple of weeks before getting “squashed” in the Weeks 3-4 timeframe.
This is in line with our thinking of the “transitional” period beginning this upcoming week. We think cold will begin to “push,” but isn’t ready to lock-in as of yet. There will be cold readily available to present more of a wintry potential with storms that track through the region when compared to this week, but we think it’s the period from 2/17 through early March that has the capability of featuring more sustained cold.
That’s a strong signal being painted by the JMA Weeklies in the Weeks 3-4 timeframe for widespread cold. Given that the MJO is forecast to swing into Phase 8 by this timeframe, along with the NAO/ AO looking to dip negative, the widespread cold look is a good idea to us during this particular time period.
This is a rather dramatic reversal from what this particular model was saying only last week- when it was bringing winter back with authority by Week 2 on. One could easily argue that even out to the Weeks 3-4 time frame that this certainly isn’t an ideal look for “stick and hold” cold to eventually push into the East.