More Southwest soaking
Thunderstorms will drench portions of the Desert Southwest again today, Sept. 24. Heavy rain may lead to new episodes of flash flooding from Phoenix and Tucson, Arizona, to Las Cruces, New Mexico, and El Paso, Texas. Rock slides may impact some mountain roads. This will delay drivers on the I-10 corridor through this region.
Yesterday, Yuma officially received a record daily rainfall of 0.53 inches, more than double the previous record. Normal rainfall for the day is 0.02 inches. Records were not broken at the Phoenix and Tucson airports, but they still received about ten times the normal amount of rain for the day. According to KSAZ-TV, as much as 5 inches of rain deluged suburbs east of Phoenix yesterday, including Apache Junction, Tempe, Gilbert and Mesa. This led to several water rescues, as reported by KNVX-TV in Phoneix.
This morning, KNXV-TV tweeted that the Salt River Project (SRP) is releasing water from the Granite Reef and Stewart Mountain dams due to the heavy rainfall.
The reason for the monsoonal rain – deep tropical moisture interacting with a strong Pacific low pressure system and the remnants of Tropical Storm Lorena (a former Pacific storm). Peak rainfall rates will be well above 1 inch per hour at times. Water levels may rise rapidly, creating hazardous conditions. Flash flooding is most likely to affect normally dry desert washes, resulting in road closures.
National Weather Service (NWS) alerts – housed inside the FreightWaves SONAR Critical Events platform – show a Flash Flood Watch still in effect through this evening from southern Arizona to far southwestern New Mexico, places where the heaviest rainfall is expected. However, other nearby areas may be added to the Watch at some point today. A few severe thunderstorms may pop up, too, producing large hail and damaging winds.
The threat for heavy rain should fade tonight, but periods of showers and thunderstorms remain in the forecast for portions of the Desert Southwest through Thursday, Sep. 26.
Severe weather in the Midwest
A severe thunderstorm outbreak is possible late this afternoon into tonight from Kansas to Wisconsin, producing large hail, powerful wind gusts and torrential rains. Scattered tornadoes may develop, and could be strong in places such as Topeka, Omaha, Des Moines, Rochester (Minnesota), Minneapolis, La Crosse and spots in between.
Additional notes
Union Pacific (UNP) railroad is still reporting outages in the Beaumont, Texas area due to last week’s major flooding. Keep in mind that this may also affect other carriers that share tracks with UNP in this region. Shippers should expect delays of 48-72 hours.
Tropical watch
Tropical Storm Karen’s eye will move through Puerto Rico and the Virgin Islands today. Yesterday, some forecast models had Karen making possible landfall in the southeastern U.S. by early next week. It’s still not impossible, but it now looks less likely that this will happen. However, the outlook could change again. We’ll keep tabs on the situation just to be sure.
Have a great day, and be careful out there!
