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Severe Storms For The Northeast U.S..; Heat And Fire Out West

A strong cold front will likely trigger severe thunderstorms and locally heavy rain on Friday from the Interior Northeast into the eastern Ohio Valley and northern Mid-Atlantic region, especially in New York state and Pennsylvania. Meanwhile, in addition to the ongoing heat wave in the West, fire weather concerns are increasing across the Great Basin into the Four Corners region. Read More >

Last week, Dan McKemy and Ryan Sharp, meteorologists at the National Weather Service in Louisville, were able to present some of their work to and learn from other operational meteorologists at the National Weather Association (NWA) Annual Meeting...this year held in Huntsville, AL.  The convention brings together partners from broadcast meteorology, universities, government meteorologists, as well as private meteorological companies.  The theme for this year's convention was "Pay it Forward".  Several sessions focused on mentoring younger meteorologists as well as lessons we learned from the bigger weather events over the past couple of years...including Hurricanes Florence and Michael as well as the devastating EF4 tornado that went through southeast Alabama on March 3, 2019.  

Ryan gave a presentation on a new way to visualize the plethora of data coming from the latest series of earth-observing satellites (GOES 16/17).  Work on the national level has provided composite imagery of multiple channels from GOES, with those composites called RGB, based on the assignment of different images a red/green/blue color.  

Lead Meteorologist Ryan Sharp giving a presentation at the NWA Conference in Huntsville.

An example RGB, in this case called the Day Cloud Phase Distinction, because of its ability to show forecasts the difference between water clouds (in the cyan color), clouds with both ice and liquid water (in green), and deeper/thinner ice clouds (yellow/pink).  To create the composite, the Infrared (IR) channel on GOES is given a red color, the visible channel is colored green, and then the channel focusing on snow and ice is given a blue color.

Meteorologist Dan McKemy gave a poster presentation on how he used some new radar forecasting techniques to make decisions on whether to warn or not warn on some rotating storms over the Ohio Valley.  Forecasters across the National Weather Service are finding more ways to study Dual Polarization radar data as we see more cases of storms since those data became available to forecasters roughly 5 years ago.  With that study, more features are being identified that could help us distinguish between tornadic and non-tornadic storms.

Meteorologist Dan McKemy presenting his case study to a crowd of meteorologists at the NWA in Huntsville.