Marine Weather and Tide Forecast for Brawley, CA

SYNOPSIS
Record temperatures are expected to continue through tomorrow, but cooling conditions will commence going through this upcoming week.
Dry conditions will persist through the middle of the week, but a much more significant cool down may be accompanied by breezier conditions and increasing rain chances going into next weekend.

DISCUSSION
The upper level pattern is beginning to transition out of a persistent ridging pattern to more flat ridging due to a weak low that has migrated into the Great Basin that is weakening the amplified ridge. However, skies remain mostly clear, as higher level clouds are situated east of the region this afternoon.
Temperatures will continue to run at record levels today and tomorrow, before more discernible cooling going through the rest of the week.

The aforementioned trough will continue to persist across western CONUS, with it even migrating into the Desert Southwest, resulting in temperatures cooling into the 90s for highs through the middle of this upcoming week. So while temperatures will continue to run well above normal, this will be the first signs of a transition to more typical fall-like conditions, especially heading into the end of the week and into next weekend.

A strong low in the Gulf of Alaska will dig into the eastern Pacific over the next couple of days, eventually reaching the Pacific Northwest by the middle of this upcoming week. This trough will cause the weather pattern to transition to more typical fall pattern conditions, as it will dislodge the ridging currently in place and push the strong height anomalies east of the Rockies by mid-week. As this trough migrates into the Great Basin and Intermountain West, current ensemble means are trending towards a deeper trough that could result in more interesting weather for the Desert Southwest by the end of this week and into next weekend.

While the overall pattern evolution continues to have a good amount of spread with this strong trough late this week, the ensembles are much more in line in regards to the deeper solution that the GEFS was advertising yesterday. All of the clusters are deeper to some degree than the clusters from yesterday, with about a 50/50 split between a somewhat progressive pattern and more amplified trough digging into the Desert Southwest by Friday.
Clusters then have a lean towards this troughing feature lingering across the region going through this upcoming weekend, which would result in much cooler (near to below normal) conditions. The latest NBM forecast reflects this trend towards deeper troughing, as this scenario would result in more favorable dynamics with a cold frontal band increasing winds across the region and higher precipitation chances. As such, more breezy conditions are reflected in the current forecast Thursday into Friday, while PoP's have increased to around 20-40% for south-central Arizona Friday into Saturday. However, it should be mentioned that due to the wide spread in the trough progression, there still remains large discrepancies in what could come to fruition, especially the temperatures, where Friday onward has as much as 15-20 degrees between the interquartile ranges.

AVIATION
Updated at 0500Z.

South Central Arizona including KPHX, KIWA, KSDL, and KDVT:

No major aviation weather concerns are anticipated through the TAF period under mostly clear skies. Winds will continue to follow familiar diurnal trends, with easterly directions establishing within the next few hours. The transition to west winds may take longer than usual tomorrow afternoon, with southerly directions favored instead for 1-2 hours during that time (between approximately 20-22Z). A few S-SW gusts into the mid teens cannot be ruled out during the transition to west winds. Otherwise, expect speeds across the terminals to remain aob 10 kt.

Southeast California/Southwest Arizona including KIPL and KBLH:

There will be periods of variability at both terminals, however, wind directions will predominantly be west at KIPL and favor a westerly component at KBLH (though varying widely from NW to SSW).
A period of stronger west winds is possible once again tomorrow evening at KIPL with some intermittent gusts into the teens. Skies will remain mostly clear.

FIRE WEATHER
Above normal temperatures will persist through at least the middle of the upcoming work week, though the gradual cooling trend continues. Daily highs below the century mark will become common by Monday. As temperatures decrease and a weak weather system moves southward toward the region through Tuesday, humidities will increase. MinRHs this afternoon will range from 5-10% across the lower deserts today and increase to around 8-15% across the region Monday afternoon. Overnight recoveries tonight and Monday night will range mostly from 20-40%, but as the aforementioned weak weather system approaches, some low-level moisture will be drawn northward over portions of Yuma and Imperial Counties, leading to good overnight recoveries up to 50-70% in those areas Monday night. Winds will continue to follow typical diurnal patterns through the next several days, though some breezy west winds can be anticipated over portions of Imperial County again this evening. A stronger weather system will move into the western US during the latter half of the week, reinforcing the cooling trend and likely bringing near normal temperatures across the region.

CLIMATE

Record highs through Monday:

Date Phoenix Yuma El Centro ---- ------- ---- --------- Oct 13 101 in 1989 105 in 1958 104 in 1999 Oct 14 100 in 2020 105 in 1961 104 in 2020

PSR WATCHES/WARNINGS/ADVISORIES
AZ...None.
CA...None.