Yesterday we had a high temp of 78 and the low was 49. We currently have 67 at 6:30 am for a warm summer-like morning. We have a thundershower near Owosso other than that there is no other rain on the radar at this time. You may see an isolated shower or storm this morning, otherwise, our warming trend continues today with highs reaching or exceeding 80 degrees. Rain chances will be mainly east of 131.
- Isolated showers/storms possible this morning Weakening thunderstorms over WI early this morning will continue propagating toward Western Michigan through the 09z-12z time frame. MUCAPE does build ahead of this activity (and is currently building as of this writing) with 1000-2000 J/kg available. However, with the LLJ fizzling out over the region these storms should continue decaying. A relatively short window for some leftover showers is possible across the lakeshore region this morning before the threat diminishes. A few storms have managed to develop early this morning on the edge of an elevated instability gradient overhead. Suffice to say, that was not expected. We are including some POPs to cover this threat and will continue monitoring trends. These will likely remain fairly isolated but could produce some hail given how quickly they developed lightning. - Risk for Showers and Storms Highest Near/West of US 131 Tonight Upstream convective development is looking very likely across Wisconsin this afternoon and evening. The main forecast challenge centers on the evolution of this activity tonight and our rain chances primarily from 00z to 06z. Upper level divergence is favored across WI today and some of this does try to work into our central and western CWA this evening. Weak LLJ orientation favors WI for development today while a more favorable shear environment exists there. More intense surface based instability will be across southern WI and northern IL (3000-4000 J/kg) but near and west of US 131 we may be able to support 1000-2000 J/kg. Of course, the environment over Lake Michigan is hostile to surface based storms right now. But... It is tough to ignore the 00z HREF guidance with respect to a) convective mode and storm motion, b) 4 hr max reflectivity trends, and c) 6 hour and 24 hour probability matched mean QPF. There is a good consensus among the members that these storms are going to make a run for at least the western couple rows of counties against Lake Michigan near and after 00z. Some members show a solid line of storms. One would think that after storms develop in WI that there would be a more southward propagation toward more extreme instability (southern WI/northern IL) and away from Lake Michigan given these storms will be surface based. However, looking at the 4 hr max reflectivity swath signals a different outcome. Neighborhood probabilities of 50% or greater for 40 dBZ echoes with some instability present are shown for a large portion of the CWA tonight. HREF/WPC guidance shows a trajectory of higher rain totals from WI toward western Lower MI with 6 hour and 24 hour QPF guidance. In fact there is a good signal for 0.50"-1.00" of rain for some locations if these storms make the trek. While we are not included in a severe weather outlook at this time (as of 3am), some storms could produce strong wind gusts and hail. Mid level lapse rates of 7.5-8.0 C/km will be present along with DCAPE of over 1000 J/kg. MLCIN could potentially be overcome depending on the timing of the storms, so we`ll need to keep an eye on things in the 00z-06z window. - A few showers and storms possible Wednesday then dry Thur/Fri It will feel pretty humid on Wednesday as dew points surge into the upper 60s and high temps reach the low to mid 80s. With an upper ridge overhead and weak surface winds, something to watch will be diurnal cumulus / lake breeze shower development. A few thunderstorms will also be possible, but overall coverage in these setups is quite low. It would seem the US 131 corridor is the most likely area for this to occur. Dry conditions are expected Thursday and Friday. - Some rain possible this weekend Frontal passage still looks on track for this weekend with some showers and thunderstorms possible. Rain does not look widespread at this time but this is still a ways out. Expect cooler temperatures into early next week.