DALLAS — North Texas is downright soggy thanks to all the recent rain. The entire spring season (March, April and May) was the 8th wettest on record with almost 20in of rainfall.
May itself was above normal by over 3in with rain falling almost every day during the last week of the month. Rain even welcomed the month of June with June 1st bringing almost 1.5in of rainfall at DFW Airport!
So why has it been so rainy recently?
The simple answer is a weather pattern called "northwest flow."
This pattern is actually very typical for late spring and early summer, but this year it has been persistent over the past couple weeks. Also, all the recent rain is on top of all the rain we saw earlier in the spring, which creates more flooding issues due to the saturated ground.
So what is northwest flow?
The weather pattern happens when upper-level high pressure moves west of North Texas. Sometimes it sets up over the 4 Corners states or sometimes farther south. This year, high pressure has set up mostly over northern Mexico.
It is named because the "flow" around high pressure is clockwise, which causes that flow to be out of the "northwest" overhead in North Texas.
When this type of pattern sets up, thunderstorms that form in places like Oklahoma, the Texas panhandle, West Texas, or even southern Kansas sometimes can ride that northwest flow into North Texas. Disturbances within that flow can kick off storms in North Texas during the heat of the afternoon and evening.
Because high pressure is not overhead, it does not squash any thunderstorm development and storms do not have a hard time forming or surviving the trip into North Texas.
If you are sick of the rain, start hoping high pressure moves overhead or closer to North Texas. That will likely happen at some point this summer. The problem is that will cause it to be hot and humid with highs reaching the triple digits. Be careful what you wish for!
