Rain Chances Return

The next weather system moves in on Wednesday and will stick around through Thursday. Deep, moist onshore flow should be enough to get the drizzle machine going around the bay Wednesday morning with occasional rain shower also possible. Overall, I think Wednesday will be a fairly quiet day with only a slight chance for a shower. The best chance of rain will come on Thursday. With the low to our southeast, counter-clockwise flow should push moisture back into our area from the east. Proximity to the low and decent daytime heating will help destabilize the atmosphere, so we’ll probably see a round or two of showers/thunderstorms moving in from the east or even being generated over the mountains. Chances will be highest the farther south you go in the KION coverage area, but activity is still possible around the bay. Overall rainfall two day rainfall amounts will be low—and in some cases, zero—but some heavier downpours will be possible if thunderstorms develop. It is a relatively complex scenario, so a certain amount of nowcasting will be necessary over the next two days.

AIR QUALITY: Good

Overnight: Passing high clouds with increasing low clouds on the coast and nearby valleys. Patchy drizzle possible around the bay. Lows in the 50s for most areas with a few higher valleys dipping into the 40s. Breezy up-valley winds slowly tapering off.

Wednesday: Partly to mostly cloudy with patchy coastal drizzle in the morning and a slight chance for a shower or two around the area. Rainfall amounts (if any) will be light. Highs in the low 60s to low 70s around the coast and low 70s to upper 70s inland. Windy up valleys late in the day.

Thursday: Partly cloudy with scattered showers and isolated thunderstorms, more numerous in the south & east. Highs in the low 60s to low 70s around the coast and low 70s to upper 70s inland. Windy up valleys late in the day.

Extended: Friday will be a transition day in the cool northwest flow, but building high pressure will send temperatures upward into the weekend. In fact, light offshore flow aloft through the weekend should yield high temperatures anywhere from 10-20ºF above normal with some coastal cities reaching the 80s and perhaps even 90s on Monday.

*Note: Any alerts from the National Weather Service in Monterey will be noted in italics above. Alerts may be edited for brevity or local clarification
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This week's normal temperatures:
--COASTAL CITIES--
LOW: 55ºF
HIGH: 71ºF

--INLAND CITIES--
LOW: 52ºF
HIGH: 86ºF
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-The outlook from the Climate Prediction Center for September 25^th – October 1^st calls for the likelihood of ABOVE normal temperatures and near normal precipitation.

- ENSO (El Niño/La Niña) STATUS: La Niña Watch
- ENSO Forecast: Transition to La Niña into the fall and persist through the winter months.
- Area drought status: Abnormally dry for areas around Monterey Bay northward. Drought-free elsewhere.
- Monterey Bay Sea Surface Temperature* as of September 18^th: 57.6ºF
(Historic Sep AVG near Monterey: 59.6ºF) -- *average of 7 buoys