Impressive overnight urban flash flood event in the Dallas/Fort Worth area with 9.46 inches of rainfall in 6-hr and 7.8 inches in 3-hr. Significant flash flooding has resulted. A 1-hr storm total of 3.01 inches was recorded at DFW with a storm total of 6.54 inches which wiped out 67% of the sites 2022 rainfall deficit in a few hours.
This afternoon/evening:
Weak frontal boundary is currently sagging into N TX and will slowly move southward today reaching a line from near Tyler to Madisonville to Georgetown by this afternoon. Air mass south of this boundary is already moist and unstable and with heating will become highly charged with energy by early to mid afternoon. Showers and thunderstorms will develop along the frontal boundary and move southward along with their associated outflow boundaries into air mass temperatures likely in the mid to upper 90’s.
After months of drought and heat it finally appears that much of the area will see some relief this week as several factors combine to bring widespread rains to the area. Scattered showers and thunderstorms will again develop along the seabreeze today…these storms will have the potential to produce lightning induced fires (as seen yesterday over east Texas). Wednesday starts the same as today, but changes begin by afternoon as a decent shortwave in the developing eastern US trough digs southward over the MS valley.
Mid and upper-level ridge is centered over the southern plains this morning, but is just far enough inland that tropical moisture is sliding NW toward the TX coast. Radar shows scattered showers and thunderstorms across the offshore waters and a few have moved inland over the coastal counties this morning. As temperatures warm into the low to mid 90’s showers and thunderstorms will develop along the inland moving seabreeze boundary.
Upper level ridge of high pressure currently located over the SW US will back westward slightly today and weaken on the eastern flank. This will allow a trough over the southern US to move westward a bit. Local radars over LA this morning show a complex of thunderstorms east of the central LA area moving westward and convection allowing models (CAMs) are in general agreement that this complex and its associated outflow boundary will continue westward toward the Sabine River today and then into east Texas this afternoon and toward the I-45 corridor by mid to late afternoon.
Upper-level ridge of high pressure will intensify slightly today and this will add 1-2 degrees to the already very hot afternoon temperatures. Afternoon temperatures of 104-106 in the excessive heat warning area can be expected with heat index values of 108-110. Elsewhere afternoon temperatures in the 100-103 range will be common with heat index values of 107-110. College Station recorded 106 yesterday which tied its 71-year-old daily record.
