As we mentioned in this week’s State of the Atmosphere, it’ll be an up and down week for storm chances along the Front Range and eastern Colorado.
We saw several strong storms develop Monday across the eastern plains, with only a few scattered brief storms during the early afternoon hours in the Denver area. Today those storm chances go up a bit, with 30-40% chances for eastern Colorado.
While the best chances for strongest storms will likely be west and again east of the Denver area, our chances will be greater as well. Precipitable Water values will be higher than what we saw on Monday -- up from ~0.6 inches Monday afternoon to 0.8 - 1.0 inches today (models have been slightly overdone for Denver). Greatest PW according to the 18z NAM will extend from Denver northeast into southwestern Nebraska.
CAPE will also be greater across northeast Colorado, with pinpoint for greatest values across the northeast corner of the state where values could climb to 1500-2500. We’ll need to watch for capping across the eastern plains, but should see the cap break later in the afternoon as outflow boundaries push east.
As for precipitation totals… Both the GFS and EURO are pretty spotty with QPF through Tuesday night across northeast Colorado, generally ranging from 0.5 inches across the Front Range foothills, to a few tenths out east. We expect enough ingredients to be in place to allow for better storm coverage -- and in combination with the time of year, could see spotty cells put down heavy rainfall at times. As is always the case, impossible to pin down exactly how much any single location will see with these widely scattered storms. Overall severe threat should be low today, but can't rule out a few storms becoming severe across eastern Colorado.
As for timing, Denver’s best shot at getting a storm will be during the early to mid afternoon hours Tuesday, decreasing into the evening. A few storms may linger in the foothills into Tuesday evening, as we also see the best chances for strongest storms developing across the northeast corner of the state by late in the day.
Storm chances decrease a bit for Wednesday, but enough moisture should be in place to keep a chance for scattered storms going. In fact, we have a chance for at least isolated storms in the forecast through next weekend, with slight better chances returning for Thursday and Friday.