9:45 PM Monday

Monday nights Rapid Refresh Smoke model really pushes the smoke back into Mammoth during the afternoon hours Tuesday….More hacking and coughing ahead….


The highly amplified pattern across the pacific and North America, responsible the for heightened fire season is still in play.  This is actually +PNA Redux. Its a very similar pattern that developed back in early September, when the Creek Fire started. The late August through early September +PNA that developed was epic in strength, as far as positive height anomaly over CA. (601dm) for those dates.  It was truly a hybrid between the Eastern Pacific High and the Subtropical Contential High at the time.  The net result was a small upper jet that developed along the western flank of the upper high along the CA Central coast. It moved up the coast and set off a lightening storm that the Bay Area and Northern CA will long remember. That storm was respondsible for the fires along the Central and Northern CA coasts.

The current pattern is minor in comparison, but is still similar in some respects. The main height anomaly is further north, so Mammoth does not get the heat, The strongest winds are over Northen Ca and are respondsible for the fires over NAPA and north. It should be noted that, the down stream effect is a cold eastern trof that the east is dealing with.  Additionally, meridional flow is playing havoc in europe with very chilly temperatures in the Alps and France.

The Current highly amplified pattern of ridge/trof, (+PNA) will break down this weekend.  By Monday a week away, a strong belt of westerlies pushes into British Columbia. Underneath the westlelies, California is still under fairly high heights at 500MB, so temps are likley to remain a bit above normal with highs in the low 70s by Monday. Lows in the 30s. With any westerly flow, well likely get smoke from any fires that are buring to our west or SW.

Looking at the ECMWF Weeklys; (long range) looks drier than normal right on through October.  It does show some polor jet related storminess the first half of NOV.  I usually take this with a grain of salt as climate models do not do very well in September and October.

Some minor changes in the ridge pattern will allow Signifacant smoke back into Mammoth Tuesday. The upper height anomaly splits in half with slightly higher heights to the south. This will be enough to create light SW flow Tuesday and import some smoke from the Creek Fire back into Mammoth. By Wednesday, higher heights once again develops to the north and the flow backs again to the NE, later in the day Wednesday. That will tend to push the smoke back west again late in the day Wednesday. Overall,  Still looking for a very warm remainder of September/Oct week head. Not much change through the middle of next week as well. However, the GFS is showing some subtropical moisture moving into Central and Northern CA about the 9th of October. That may bring some light rain to our area.  Updates on that next week.



Dr Howard and the Dweebs…………………..:-)