Serious Heat & Humidity Continues In The Week Ahead…
An expansive upper level ridge will keep many across the eastern half of the country very hot and humid over the upcoming week. The worst of this particular heat wave, relative to average, will center itself over the Great Lakes and Northeast.
More specific to central Indiana, daily highs in the lower to middle 90s and overnight lows in the lower to middle 70s will continue into late next week. For the most part, this is a dry pattern, as well, BUT there will be a few exceptions.
The first of such arrives Sunday evening into Sunday night with the potential of a line of showers and thunderstorms rumbling into the state. We note high resolution models weaken this line of storms as it arrives into central Indiana (likely after dark Sunday), but we’ll keep an eye on things. As things stand now, the western half of the state stands the greatest risk of getting meaningful rain Sunday evening.
Thereafter, additional isolated to widely scattered storm coverage is possible- primarily during the afternoon and evening hours, but more than not will remain rain-free. 7-day precipitation totals check in this morning in the 0.25″ to 0.75″ range.
In the longer range, we should begin to see a transition to “less hot” 🙂 conditions next weekend followed by a more significant pattern change for the second half of July as the upper level ridge retrogrades west, centering itself over the Rocky Mountain region.
Not only will this likely lead to a cooler second half of July, but should also offer up an increasingly active and wetter northwesterly flow for our immediate region.
In addition to a wetter pattern, we would also want to pay attention to the potential of a gusty storm complex or two riding southeast around the hot dome off to our southwest.
In closing, the JMA Weeklies led the charge in the idea of more active times returning in June, and the combination of GFS and European ensemble data suggests they had merit. With the added bonus of having the MJO on our side, it’ll be hard to avoid a change of the guard towards an overall wetter pattern in the weeks ahead. Perhaps Alberto’s remnant moisture is only the beginning…
Back here on the home front, a quiet start to our Monday will turn stormy at times this evening as the front nears. We think best coverage of showers and thunderstorms will come between 5p and 10p. There will be some winners and losers when it comes to rainfall amounts by midnight. Some can expect over an inch in the stronger storms while others may only see a tenth of an inch, or so. Something that must be taken into forecasts moving forward is the tendency of most model data (high resolution and global data alike) to “over forecast” rainfall amounts as of late. Also of note is for the potential of a couple of strong to severe storms to develop this evening. We always have to be wary of fronts draped across central Indiana as they’ve been known to help tornadic activity spin up. We’ve lost count of how many slight risk days with warm fronts nearby that turn busy… If you’re planning to be outdoors this evening, please have a means of receiving the latest watches and potential warnings that may be issued.
High pressure will build in for the midweek period and supply plentiful sunshine along with continued warmer than average conditions. Overnight lows will fall into the upper 50s (couple of degrees above average) with the drier air mass in place, but afternoon highs will continue to climb into the lower and middle 80s (around 10 degrees above average).
Longer term, thoughts are shifting towards the open to meteorological summer (where is this year going?!). The GFS ensemble suggests the overall warm pattern remains intact as we open a new season with widespread warmth expected through the first few days of the June.
Otherwise, look for considerable cloudiness and highs topping out in the lower 70s today.
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.