It is not uncommon for tropical moisture to reach Colorado, but it is even rarer for the state to obtain moisture from previous hurricanes. Colorado will soon see moisture from Hurricane Nora, and some areas of the state have already implemented flash flood warnings.
Hurricane Nora is expected to move near Baja California and along the Gulf of California this weekend, and moisture will spread to the southwestern United States in the middle of next week. Therefore, the possibility of flash floods in the Four Corners area will increase. pic.twitter.com/Ov4ODoRdvC
— NWS Weather Forecast Center (@NWSWPC) August 28, 2021
The area formerly known as Hurricane Nora is now only a zone of deep tropical moisture. Due to the high-level pattern of the atmosphere, moisture will soon come to us. When it travels from the Southwest Desert to the state, the system will cause serious flooding problems in the Four Corners area. Earlier this week, California and Arizona had issued flash flood warnings, and as of Wednesday morning, Colorado had also issued flash flood warnings.
On Wednesday, San Juan, Colorado will begin to see heavy rain coming in, which will pass through the west slope throughout the day. The system will move slowly, which will increase concerns about flooding because storms will also move slowly. A large amount of rainfall may drop in a short period of time, which will not only cause flooding, but also cause mudslides.
Tropical moisture (from former Hurricane Nora) is expected to enter Colorado on Wednesday, which means the possibility of flash floods is back.
-⛈Rain or☀️Shine I am Andy Stein (@AndySteinWx) August 30, 2021
There was a threat of rain in all mountainous areas throughout the day on Wednesday, with burn scars and high flood threats near the slit canyon, especially in the afternoon. For the western part of Colorado, Wednesday will be the day most likely to rain.
On Thursday, this humidity began to enter the front mountain range, bringing some much-needed rain to the I-25 corridor. For several weeks, the drought has been slowly returning to the forefront. There will be showers and several storms throughout the day on Thursday, and the humidity will linger until Friday. In general, it is expected that there will not be a lot of rainfall in the urban corridors, so flooding will not become a major problem. The foothills and frontier mountains may encounter some problems, depending on the location of the downpour.
Most areas of Colorado had a deficit of 50% above normal levels in August, so this rain is a welcome sight. Throughout the weekend, there may be showers and storms across the state, but overall, the state will be quieter. A longer-term forecast model shows that the weather will be more active throughout the state next week.
As the rain falls, the clouds will also bring cool temperatures to the area. The temperature across the state will drop below the normal value, so that the intense heat we experienced has been well alleviated. This weather will also help disperse some wildfire smoke in California and reduce fire hazards in Colorado.