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In Brief:
A strong short wave and in-place moisture will interact to create a lot of thunderstorm activity today (Sunday) in the mountains that will merge into a couple of lines of occasionally severe storms this afternoon. After that, we have seasonable weather this week with mostly dry conditions.
9/9 11am update:
The storms performed as advertised dumping 1/10th to a quarter inch across our fair city (Figure 1 update). Storm reports so far (Figure 2 update) show most of the damaging wind reports came from the Western Slopes but there seem to have been few tornadoes out to our east. Wild times!
End 9/9 11am update.
Forecast Discussion:
There is a blob of notable instability approaching the state today (green circle over Utah and neighboring states - Figure 1). This is being created by a strong short wave coming in from the west (Figure 2). These ingredients have led the SPC to paint a bullseye of Marginal (1 on a scale of 1-5) and Slight (2 on a scale of 1-5) severe weather risk over the Front Range and NE portions of our state (Figure 3). The primary risk from the (forming) lines of nearly continuous thunderstorms will be strong winds, but some hail is possible as well.
Storms will fire around 12p-1pm in the mountains and begin to fill in hitting the urban corridor between 4-7pm (Figure 4) but a few storms will be possible all afternoon and in spots later in the evening.
The Longer Range Forecast:
We resume our gentle glide into Fall on Monday with some comfortable weather by mid-week. There still is a 90F in the distance (Figure 5).
