At the last NARC meeting AE5P recommended that we use 6 digit Maidenhead Grid Location for all SKYWARN events. After Army's brief training session, I pulled up DeLorme Street Atlas USA 2004® and started playing. Using the draw feature I was able to create the 24x24 sub grid for EM21 and here are the results.
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The Entire EM21 Grid.
EM21 centered on the city of Nacogdoches, TX.
EM21 centered on the city of Lufkin, TX.
US Grid Square Map (Thanks ICOM!).
Grid Square Maps of Texas and the other states in the 5th Call District.