This content was originally published by the Longmont Observer and is licensed under a Creative Commons license.
Forecast Discussion:
The early moisture interacted with afternoon heating to give Longmont a loud thunderstorm Friday afternoon. We didn't receive much rain, but it poured for a few minutes. By evening, the center of Bud was just into Mexico (Figure 1). The deepest moisture is still down in New Mexico Friday evening.
We were going to watch the precipitatable water values on the soundings.
It was 1.19cm Thursday AM (which is 0.47 inches of water). The Thursday PM precipitatable water value had already risen to 1.69cm / 0.67 inches. From Figure 2, it is at 1.78cm (0.70 inches). Models are showing 1.25 to 1.50 inches of precipitatable water by Sunday over the region. This is far above normal for June - it is similar to what one sees in the late Summer, sometimes.
By this afternoon, the moisture will be arriving. You can see the front that will push down later in the day (Figure 3). This front will matter more on Sunday as it advances again. Rain is definitely hitting a LOT of the fire regions. Figure 1 shows the flash flood watch that is already in effect in the SW corner of our state. Burn scars will flood easily and a lot of debris can be washed into waterways quickly after the fires.
As winds increase, the smoke should blow off to the northeast a bit quicker (Figure 4). Rain will help clear the air as the weekend wears on (and, hopefully, the lower temperatures, higher humidities, and rain, will diminish fire activity).
The longer range forecast:
The WRF has the next 48 hours of precipitation for us. Longmont is in the 0.5 inch to 1 inch area by Sunday morning (Figure 5).
Looking out to Wednesday PM, the total precipitation for Longmont predicted by the GFS is around 1.5-2.0 inches (seems extreme, but it has been consistent). Note the 5 inch totals above Boulder. Yikes - if true. (Figure 6).
The WPC model, for this time window, gives us almost 2.5 inches of rain. Rainfall above Boulder approaches 3 inches between now and Wednesday night (Figure 7).
More tomorrow. Hopefully I'll be typing in the rain.
And happy Father's Day (early) for all the Dads out there. (We're going to a Dad-themed movie ourselves.)
