An upper level low pressure system will track northeast today into tonight, and as it does, look for more numerous showers and embedded thunder to develop. Some localized heavier downpours are a good bet this evening across central Indiana.
Otherwise, look for considerable cloudiness and highs topping out in the lower 70s today.
While we’ll have to contend with a few showers Saturday, overall, the day should be drier compared to today and what lies ahead Sunday. Speaking of Sunday, we’re monitoring the potential of a couple of storms reaching strong to severe levels to close the weekend. The Storm Prediction Center includes central portions of the state in a “marginal” risk of severe with their update Friday morning. It wouldn’t surprise us if a portion of the marginal risk is upgraded to a “slight” risk in future updates. We’ll fine tune storm timing over the next 24 hours.
As we look ahead to the end of May, there really aren’t any significant changes to the overall warmer than normal theme we’ve enjoyed so far this month. Longer range guidance off of the European ensemble continues to support broad scale upper ridging across the Mid West and Ohio Valley and a corresponding warmer than average regime. From a precipitation perspective, the next couple of weeks do look more active compared to the dry start to the month. Case in point, the balance of the upcoming week will be dominated by a stalled frontal boundary. While we’ll have to fine tune exactly where the front stalls, daily chances of showers and thunderstorms (scattered fashion) can be expected.
2.) Overall, a drier air mass will build into central Indiana today and Thursday (cooler, too) before moisture returns to close the week. Scattered showers and embedded thunder are more likely Friday and again late Sunday into Monday.
3.) Looking ahead, we notice a more active pattern is presented off the overnight GEFS model. The heat ridge backs west and sets up a busy “ring of fire” pattern with a northwest flow aloft across our region. We have a ways to go before developing consistency and overall confidence, but this is at least an encouraging sign. The end result, should this come to fruition, would be a significantly wetter open to June.
At the surface, all three major global models agree on warmth in the long range period, including the GEFS, EPS, and CFSv2:
Guidance suggests below average precipitation during the period. With broad scale ridging in place, we agree on a drier theme compared to normal. While trying to put our finger on the flip from the prolonged cold to warmer was difficult to nail down from March and April, May always looked like a drier than average month from several weeks out. (One note is the potential of active times across the Great Lakes region as “sudden summer” gains steam to the south and stubborn chill refuses to let go to our north. The gradient would promote heavier than normal precipitation relative to average).
Given the agreement in the data, along with some additional pattern drivers, we continue to believe the medium to longer term period (including mid and late May) will feature an overall warmer than average pattern along with drier than normal conditions.