Friday, June 30, 2017

Combustible Fourth of July Weekend Forecast

With the Fourth of July next Tuesday, we have a holiday weekend on tap.  My forecast for the weekend can be summarized in one word.  Combustible.

The Brian Head fire gets everyone's attention, but both lightning- and human-sparked fires have been quick to flare up across the state.  Despite a good snow season, fire danger is rated as moderate to high across northern Utah and very high to extreme across southern Utah.

Source: USFS Wild Fire Assessment System
Precipitation has been scant across the state for several weeks, with 50% or less of average falling across much of the state over the past 60 days.

Source: NOAA/NWS
The past 60 days have also been unusually warm.  For example, the period from 29 April through 29 June is the 2nd warmest on record at the Salt Lake City International Airport (ignore the first year in the graph below as it contains several missing days).

Source: NOAA Regional Climate Centers
This has led to tinderbox conditions across most of Utah, with energy release component indexes, a measure of how hot a fire could burn, remarkably high across southern Utah and well above median across most of the rest of the state.  

Source: https://gacc.nifc.gov/gbcc/predictive/ERCMap/RAWS_ERC.html
Now, lets turn to the forecast.  After a refreshing night last night, we're moving into nuclear summer for the weekend.  Forecast highs for the Salt Lake International Airport are in the mid to high 90s.

Source: NWS
St. George?  Triple digits.

Source: NWS
Basically, we are in the Venn diagram overlap region of dangerous fire conditions, hot weather, and a fireworks laden holiday.  If you are wondering, information on fireworks restrictions for Salt Lake County is available here and for the state here.   

No comments:

Post a Comment