Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 412 AM EDT Thu May 12 2022 Valid 12Z Thu May 12 2022 - 12Z Sat May 14 2022 ...Rapidly developing low pressure system will bring rounds of heavy rain, severe thunderstorms and strong winds across the Upper Midwest and northern Plains through Thursday night... ...Summer-like heat from the southern Plains to the Great Lakes and northern New England will continue to challenge daily records... ...Unsettled weather to enter the Northwest as well as over the East Coast during the next couple of days... ...Another day of critical fire danger across central/southern High Plains before conditions ease on Friday... An anomalous weather pattern will continue to bring active weather across the northern Plains as well as the Pacific Northwest, anomalous heat from the midsection of the country to the Northeast, while a low pressure system is forecast to move back toward the East Coast. Starting in the midsection of the country, upper-level energy moving through a persistent upper trough across the western U.S. will interact with a stalled front to result in a rapidly developing low pressure system to sweep through the northern Plains today and into tonight. Rain is forecast to expand across the northern High Plains and become heavy by tonight as the system rapidly intensifies just to the south. Strong to severe thunderstorms will also impact the upper Midwest during the early morning hours ahead of a lifting warm front. As the low pressure system further intensifies later today, a strong cold front will sweep across the northern Plains, triggering another round of strong to severe thunderstorms as a result. These storms are forecast to reach into the upper Midwest by tonight with locally heavy rain and instances of flash flooding possible. By Friday, the main low pressure center is expected to enter south-central Canada as the attached cold front stalls across the upper Midwest and trails back across the southern Plains. The severe weather threat is forecast to diminish slightly on Friday but additional rounds of strong thunderstorms can be expected to reignite near this frontal boundary into Saturday morning. Ahead of the western U.S. upper-level trough, an anomalous ridge anchored over the Great Lakes to northern New England will lead to widespread above average temperatures. Highs 20+ degrees above average are forecast for today and Friday across the Great Lakes, Interior Northeast, and northern New England, which equate to temperatures into the 80s. Highs into the 90s will reach as far north as Iowa today, which combined with heat indices approaching 100 degrees, has prompted Heat Advisories to be issued across parts of the Midwest. Meanwhile, much of the southern Plains will continue to experience summer-like warmth and highs into the mid-to-upper 90s. Dozens of daily high temperature records will be challenged once again today throughout 16 states spanning from Texas to Maine. The anomalous early-season heat is anticipated to relax slightly on Friday (outside of northern New England) as the cold front and associated thunderstorm activity enters further into the Midwest and central/southern Plains. As the previously mentioned storm system strengthens over the central High Plains, gusty winds and low relative humidity will make for another day of dangerous fire weather conditions over the central/southern High Plains before conditions ease on Friday. Elsewhere, a retrograding low pressure system and associated moisture from the western Atlantic is forecast to begin entering the Southeast today. Areas of showers and isolated thunderstorms will lead to unsettled weather along the East Coast from southern New England to northeast Florida. Rain is also expected to enter the Northwest as a frontal system swings into the region with locally heavy rainfall possible along coastal regions of Washington and Oregon. Snow is likely in the higher elevations of the Cascades before spreading into the northern Rockies by Friday morning. Another system from the Pacific is forecast to arrive with a new round of preciptation moving into the Pacific Northwest late Friday into Saturday morning. Kong/Snell Graphics are available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php