Summary: October 16, 2018
Water Year 2019 has started off very nicely for the Intermountain West with much of the area receiving at least 0.50" of new precipitation this last week. Much of western Colorado and southern Arizona saw widespread amounts of 1.00-2.00" of precipitation, bringing monthly totals for the Upper Colorado River Basin in the 2.00-4.00" range.
Thanks to the precipitation, streamflow has continued to increase. The majority of streamgages are now in the normal category and the number of record low flows has decreased even more. There are still a significant number of gages in the below normal and much below normal flows. These will probably hold on for quite a while.
The eastern plains of Colorado also received another good bit of precipitation. Last week saw the first widespread snowfall along the Front Range, out to the border. This continues to help the recently planted winter wheat, which is in good shape going into winter.
The outlook for the next week starts to dry out a bit. Much of Colorado is forecast to see little to no new precipitation. The San Juan Mountains might see 0.20", but quickly decreasing in the lower elevations, with no precipitation forecast for eastern Colorado. Southeastern Utah and Arizona could see between 0.50 to 1.00" over the next week.
Upper Colorado River Basin: Last week, the D4 in central Utah was improved to D2. This should have only been a 1-cat improvement. So we are recommending D3 be added back into central Utah, connecting to the existing D3 in southwestern Utah.
Improvement of D3 to D2 in Mesa County, CO, Grand County, UT and just touching northern San Juan County, UT is recommended. This area received more precipitation, in the 1-2" range. This bring totals to 2-4" for October, which is already 2-4" above normal. SPIs have improved to near normal or positive out to 6-months. The gradient between D2 and D4 is now very tight, but with the Grand Mesa, the elevation changes quickly and there are still very dry SPIs on the Mesa.
Eastern Colorado: Recommending a 1-category improvement along the Larimer County/Jackson County line, extending into Grand County. Last week's snowfall was welcomed and short-term SPIs have improved significantly. Boulder County also received precipitation, however it wasn't as heavy and SPIs are still showing dryness, and the current situation is justified.
The Drought Monitor Author has suggested improvements in southeastern CO and northeastern NM. We agree with the Colorado improvements. A rough sketch is shown on our map.
Visit the U.S. Drought Monitor