textproduct: San Diego

SYNOPSIS

Monsoonal moisture will decrease this weekend, with a slight chance of showers and thunderstorms for the mountains and lower deserts returning for Monday afternoon. Above average high and low temperatures will continue through next week. Widespread moderate to locally major HeatRisk for the coast, valleys, and mountains except near the beaches and for the higher elevations in the mountains, with major to extreme HeatRisk for the lower deserts.

..UPDATED AVIATION DISCUSSION

Today through tomorrow night...

A strong ridge remains in place through this weekend, with temperatures remaining around 5 to 10 degrees above the seasonal average for this time of year. There will be some monsoonal moisture passing through the mid levels over the region by later on which may allow for a rogue shower or two to develop over the mountains, although it will likely struggle to develop into a thunderstorm, given the lack of instability and overall flow. The marine layer as of this morning has struggled to form with only patchy ceilings along some of the coastal sites, and this will be the case again for tonight. Be advised of all heat products issued, and be sure to stay hydrated!

Monday through Friday...

There will be a slightly better influx of monsoonal moisture for Monday through the rest of the week, although the mid-level flow will still not be favorable for afternoon shower and thunderstorm development to be significant. However, there will still be the chance of isolated showers and thunderstorms each afternoon over the mountains and adjacent deserts, especially by later in the week. It will also remain very hot, with only a slight cooldown on Monday and then gradually increasing towards the middle of the week as the ridge remains stationary and locked in over the desert southwest, translating to the persistence of high temperatures remaining on an average of 5 to 10 degrees above average throughout the rest of the work week. The marine layer will likely have similar results, with struggles to form overnight and likely impacting only the coastal areas for the most part.

AVIATION

230935Z...Coast...Patchy low clouds along the immediate San Diego Co coastline will continue to gradually become more widespread for coastal areas until just after sunrise. Moderate confidence on cigs impacting coastal SD between 10-15Z with bases 500-1,000ft MSL. Lowered vis 2-4 SM expected for higher coastal terrain, locally >= 1 SM. Clouds clear over land by 16Z. Similar bases are expected for patchy low clouds late tonight, with highest chances for cigs 12-15Z Mon for southern SD Co including vcnty KSAN.

Otherwise...VFR conditions through the TAF period with FEW-SCT clouds AOA 20,000ft MSL expected later today.

MARINE

No hazardous marine conditions are expected through Thursday.

BEACHES

A 4-5 foot southerly swell at 13-15 seconds will move into the area Wednesday and Thursday, leading to elevated surf for the south facing beaches of northern San Diego County and Orange County. Breaking waves of 4 to 6 feet are likely, with the potential for local sets to 8 feet. Surf gradually subsides on Friday.

SKYWARN

Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions.

SGX WATCHES/WARNINGS/ADVISORIES

CA...Extreme Heat Watch from Tuesday morning through Friday evening for Apple and Lucerne Valleys-Orange County Coastal Areas- Orange County Inland Areas-Riverside County Mountains-San Bernardino County Mountains-San Bernardino and Riverside County Valleys-The Inland Empire-San Diego County Coastal Areas-San Diego County Mountains-San Diego County Valleys- Santa Ana Mountains and Foothills.

Heat Advisory until 10 AM PDT Tuesday for Orange County Inland Areas-Riverside County Mountains-San Bernardino County Mountains-San Bernardino and Riverside County Valleys-The Inland Empire-San Diego County Mountains-San Diego County Valleys-Santa Ana Mountains and Foothills.

Extreme Heat Warning until 8 PM PDT Friday for Coachella Valley- San Diego County Deserts-San Gorgonio Pass near Banning.

PZ...None.