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Forecast Discussion:
The front is in place Friday afternoon with temperatures still in the 40's F at noon (barely) - Figure 1. Hurricane Rosa is lurking to our distant southwest and is still expected to come our way. Overnight Friday, the front pushed east on southwest flow aloft and warm dry air poured back into the state (Figure 2).
We will be quite warm today again.
The longer range forecast:
By Monday night (Figure 3) the trough in the west picks up the remains of Rosa and drives it into Arizona and eventually Utah and western Colorado. Figure 4 is the surface precipitation forecast for the same time from the GFS. There is a lot of water hitting the desert southwest (over 5 inches in places!).
The National Hurricane Center's 5 day forecast brings Rosa up to near Yuma early Tuesday AM. Moisture will be pulled out ahead of the center of circulation (Figure 5). Figure 6 is the longer range track from various models - they are trending more to the northwest corner of our state than yesterday's runs. Still, Figure 6, the GFS, gives us a bit more water (this is through next Monday). The next 10 days, with Rosa and later storms, water seems to add up to almost an inch. Here's hoping!
