wxgeek's weather-Bad fire weather forecast

After some more seasonal temps and RH conditions today, models indicate an upper ridge will build back over CO through the end of this week, which will increase temps and lower RH values between now and the weekend. There is a slight chance for isolated showers/thunderstorms this afternoon and evening, but any precip would be light, and it is more likely to have strong outflow winds and possible dry lightning from any storms that do develop, so not a help to firefighters. Winds at the surface will be from the south to southeast across most of eastern CO at 5-15 mph, with some gusts to 15-20 mph this afternoon.

For the remainder of the week, isolated showers and thunderstorms will be possible Tuesday through Friday, although best chances for any accumulating precip will be over the Plains east of I-25. Any storms that develop over the foothills will likely cause more problems with winds and lightning than any help with rainfall. Temps expected to be well above seasonal norms by late this week and into the weekend, with low RH values and gusty winds at times, so pretty bad fire weather conditions will persist into the weekend. Long range models offer some optimism early next week with an upper trough moving into the northern Rockies which will cool temps and offer better rain chances early next week, before more heat and low RH values return later next week. In general, models indicate the remainder of June will be warmer than usual with below average precip. To date we have received 0.50 inches on Conifer Mtn, whereas we average 2.0 inches of precip in June. Outside of areas that received abundant thunderstorm rains last week, the rest of the state remains very dry with burn bans in many counties. Extreme caution should be used when using any device that can create a spark, including but not limited to chain saws, off road vehicles and firearms.

High Park Fire Area - winds will be from the south to southeast today at 5-15 mph with gusts to 20 mph this afternoon. Fire movement will generally be to the north, but movement is possible in all directions due to terrain forcing and upslope daytime flow. Temps will increase later this week and RH values will remain low into this weekend. Flow aloft will remain westerly to southwesterly so smoke plume direction will generally be to the east to northeast. At night, as inversion forms low level smoke will disperse with nighttime down slope flow, so most of the Front Range and foothills as well as Plains will continue to be affected by smoke and haze this week.

A note about the cause of the fire being reported in several newspapers as due to a lightning strike early Saturday morning. there were no thunderstorms in the area Friday night or Saturday morning, the fire was simply reported early Saturday morning. I took a look at all lightning strikes over CO from Wednesday to Friday last week, and the only chance I saw was from a very small cell around 3 pm on Thursday June 7 that formed over where the fire was initially reported. I could not find any actual lightning strikes over the area, but it is possible the lightning detection network did not report a strike, as the reported efficiency is around 95%, and can be lower in mountainous terrain. Until a more thorough investigation is performed, I would call this initial cause a theory at this time. If there was indeed a lightning strike, it is possible the stricken material smoldered until stronger winds fanned the flames Friday night. This does bring up an important lesson for all foothill residents, that after any thunderstorms, keep a watchful eye out for any smoldering for several days afterward.
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"Climatology is what you expect, Weather is what you get".

"It is better to be roughly right than precisely wrong".