Once again folks in the Rio Grande Valley woke up to record cool temperatures.
Clear skies, weak winds and dry air conspired to create a near perfect environment for radiational cooling overnight allowing temperatures to fall nearly 20 degrees below normal.
Temperatures dropped so far that two very old records were easily broken. Harlingen woke up to 52 undercutting the previous record of 55 set back in 1912 while Brownsville bottomed out at 54 or two degrees below the record also set back in 1912.
The upper valley was cool but not cool enough: McAllen called in with 53 falling short of the record set in 1945 of 51.
Warmer days, higher humidity and stronger southeast winds will put an end to the aggressive overnight cooling. Forecast lows are in the mid to upper 60's as early as tonight.