Tuesday, May 20, 2014
Memorial Day Weekend will be nice across all of the Midwest, temperature-wise with highs in the 80s for much of the area. A few strong to severe thunderstorms are possible across the entire area on Sunday and Monday as a disturbance passes through, stay tuned for severe weather updates for the Memorial weekend.
Below are the current CAPE values, basically a general telling of the amount of energy a T-storm has to work with at the given time. It can be increased by surface warming and environmental factors.
Below is current (5:00CDT) Bulk-Richardson number across the Midwest, a basic composite value for severe weather.
It is the product of 100mb MLCAPE and 0-6km magnitude of the vector difference (m/s; often referred to as "deep layer shear") accounts for the compensation between instability and shear magnitude. Using a database of about 60,000 soundings, the majority of significant severe events (2+ inch hail, 65+ knot winds, F2+ tornadoes) occur when the product exceeds 20,000 m3/s3.
Monday, May 12, 2014
Saturday, May 3, 2014
The warm sector (to the east of the
cold front and to the south of the
warm front) will see highs in the 70s and 80s area wide. This will likely be the first 80 for many in the Midwest. With dew points on the rise and ample surface heating, the atmosphere will become prime for severe weather, with CAPE values approaching 3000 J/KG from Wisconsin on south. A severe weather outbreak is certainly possible on Thursday in the warm sector and ahead of the cold front. We will have to see just where and when this system sets up. The 00z GFS (below) is firing up some thunderstorms for Thursday evening along the cold front. While the front will not bring much in the way of colder air, it will create necessary lift and convergence to develop strong to severe thunderstorms with heavy rains. Back to the temperatures, the chart above is forecasted high temperatures for late next week off the 00z GFS model run. Another temperature map is attached below coming off the European weather model, showing a major range of temperature across the Midwest. The barrier between warm and cool with depend solely on the track of the system mentioned above, either way warmer weather and a kick start to severe weather is on the way for the first full week of May.