THE CASE FOR FIFTIES....
After talking about it for days, the long advertised storm is finally coming together. While it has a wintry side, it's also got one that's springlike and capable of bringing thunderstorms and 50 degree highs to my southern counties.
The warmth is already making itself known with highs today hitting 49 hear in Cedar Rapids. What a dramatic change from the 5 consecutive below zero mornings earlier this week. We're now at 11 sub-zero lows this month. The average low ending the 19th was 1.6 degrees.
Sunday will be one of those weird days around my area where the warmest temperatures won't arrive until midnight. The reason why is tied to a warm front attached to a northward moving low pressure. The speed of the system won't get the true warm sector into the region until Sunday night. You can see the low pressure center north of Cedar Rapids Monday morning.
By then the EURO is forecasting temperatures in the 50s over much of SE Iowa and northern Illinois. The NAM and 3K NAM are not as warm but I think they are struggling thermally so I have discounted their cooler solutions for now.
With dew points forecast to reach 50 there will be enough instability for scattered thunderstorms, especially Sunday night or early Monday morning. Here's dew points at 6:00am Monday.
The moisture and incoming warmth results in widespread CAPE which points the way to where thunderstorms are likely to occur.
For my area, it looks like the heavier rains will hold off until late Sunday or Sunday night. Up until that time the rest of the day looks cool and breezy with occasional light showers or drizzle. Pinpointing the heaviest precipitation in the warm sector where my area resides is always a challenge, especially when convection is involved. I like the track and timing of the EURO so I've chosen that model to represent total precipitation.
The EURP shows this for snowfall. Winter storm warnings and advisories are out for areas just to my north.
The storm will wind down late Monday and Monday night with some wrap around snow showers. Little if any accumulation is expected around my area. Maybe a dusting in the W/NW. Fifties and thunderstorms! Nothing like a spring preview in the middle of winter! Roll weather...TS