Severe Weather Today, ushering in cooler air.

Today will be another one of those days severe weather will return as a cold front moves into the area and encounters the hot humid airmass. This has very well become the new normal in Manitoba and it is a hard fact to swallow, though all we can do is just take it as it is. Hopefully we can enjoy some warm dry weather in September before summer is over.

There will be another day of severe weather today and it is already starting up in Southwest Manitoba, however this is not the main event. A high risk is present in the southeast part of the province including Winnipeg, areas in the interlakes have a moderate risk of severe weather where high instability levels present. Although a slight risk of severe weather is present further west in the Brandon area into the parklands with ongoing storms today with lesser instability present. A frontal system riding along the ridge will encounter a hot and humid airmass that is in place in the region.

Sufficient moisture will be available for storms today with dewpoints in the high teens and low 20's, along with PWAT values in the 30 to 45mm range. Large instability in the atmosphere will also be present today with Lifted Indicies in the -7 to -11 range, MLCAPE 1,000 in Far Northern South MB to 2,500 and 3,500 in the south as well as MUCAPE 2,000 to 4,000. Bulk Shear values in the 40 to 65knot range and very little EHI. The trigger will be our Cold Front moving through.

Discussion: Severe Thunderstorms are ongoing this morning ahead of a trough and they will move east northeast throughout the day into the interlakes, another cold front will be moving through later in the day today with the hot and humid airmass. It will remain capped for much of the earlier half of the day in moderate to high risk areas with storms struggling to develop, however the cap will slowly erode throughout the day in the Red River Valley and Southeast MB. Once the cold front goes through the cap could be eroded enough for storms to develop especially west of and in the Red River Valley supercells could very develop given extreme instability levels present that are building through the day. In early storm modes all severe weather will be possible from heavy rainfall rates in excess of 40mm flooding will be possible, hail from loonies to tennis balls possible with larger hail possible in southeast MB and the southern Red River Valley  but still a potential for golf balls or smaller in the central and northern Red River Valley in to the interlakes. Winds in excess of 90 to 100km/h, frequent dangerous lightning and tornadoes as possibility in discrete supercells but a small chance compared to what we have seen earlier this year. Once storms organize into a line (depending on where they form) either from west of Winnipeg or east of the city they will pose as mainly a straight line damaging wind threat and hail threat as they move east into the Red River Valley or Northwest Ontario. Storms should clear by late evening to after midnight.

Cooler and drier weather is expected tomorrow into Thursday and the weekend.