Severe wx threat this mothers day

[WXBUFFJIM]

Severe weather threat appears to be increasing with time as we head on through the next couple of days. Today an upper disturbance will eject east into the northern Plains and the upper Midwestern United States resulting in a severe weather threat including isolated tornadoes. Another area of concern will be from the Mid Atlantic northwestward through lower Michigan where a slight risk of severe thunderstorms will occur along the warm front and along any thunderstorm outflow boundaries. The key to the forecast today back east will be where exactly is the focus for thunderstorm development??? Yes the warm front will be one area of focus. But we have a leeside trough east of the Mountains into the Mid Atlantic. We have bay and sea breezes to consider and also some other thunderstorm outflow boundaries to consider. Definitely something to watch as we head on through the day.

The next question is what are the primary severe weather threats??? across the northern Plains, very large hail and isolated tornadoes will be the primary threats today as an upper disturbance ejects east into the northern Plains. This batch of storms is expcted to morph into a severe weather complex and track east into the Great Lakes areas later tonight with damaging wind and hail the main threats. But there has also been radar estimates of 6-8 inches of rain from southern Wisconsin into central Lower Michigan. This area does not need the rain at this time. Unfortunately more is coming, hence flooding threat could be quite high from this storm system. More showers and storms are expected in this same area through Thursday at the very least. Flooding could be one of the highest most dangerous threats as the week wears on across the north central United States. Severe weather threat will also increase throughout the week across the central US with tornado threat increasing Wednesday night through Thursday across tornado alley.

Further east, the problems will be more isolated, but just as dangerous today as a warm front slowly moves to the north. This warm front more or less is quadstationary. So it's barely moving if at all. This front currently extends from southern lower Michigan eastward through northern Ohio and into central and southern Pennsylvania. Along this boundary. showers and storms will develop this afternoon and rapidly become severe with strong daytime heating in place.

Southern Michigan, northern Indiana and northern Ohio will be upgraded to a slight risk of severe thunderstorms because of strong heating at the surface combined with a quadstationary front in the vicinity. Main threats will be large hail and high wind in this area. Further east and south across the Mid Atlantic, the quadstationary front becomes a warm front, hence thunderstorms developing along that warm front this afternoon from Pennsylvania through New York City with hail and high wind the main threats. Heavy rain and dangerous lightning will also be big dangers with this batch of storms, which is expected to develop later this afternoon.

Further south from DC to Baltimore, there is very little focus except for a leeside trough east of the mountains and possible bay and seabreezes and old outflow from earlier thunderstorms. Hence storms could develop just about anywhere across southern PA, Maryland, northern Virginia, and the Delmarva Peninsula. Hail is the biggest threat with the strongest storms with a lesser threat of damaging winds. Most of the storms back east should gradually weaken later tonight given the loss of strong daytime heating and instability.

Jim