Moisture from a decaying tropical storm and milder-than-average ocean temperatures sent humidity levels in drought-stricken California soaring this weekend. It also sparked multiple rounds of thunderstorms in San Diego and the San Francisco Bay area.

Tropical moisture from what was once Hurricane Dolores prompted flood watches to be issued across the Southwest, from California to Utah and western Colorado.

See also: Fighting face to face with wildfires in California

Los Angeles and San Diego set all-time monthly rainfall records for the wettest July, after showers and thunderstorms moved through the cities on Saturday. In San Diego, 1.03 inches of rain fell on Saturday, breaking the July single-day record of 0.83 inches, set back in 1902, and the record for all of July, which was also set that year.

In addition, Los Angeles broke its record for the wettest July when it received just 0.36 inches on Saturday.

July rainfall is rare in coastal California, making the heavy rains of this weekend extremely unusual. In fact, any rainfall at any time is rare in California these days, with the state entering its fourth year of a historic drought. The rain in San Diego on Saturday was more than that city saw in all of January 2015, which is typically its second-wettest month.

According to the National Weather Service, more showers and thunderstorms are likely in southern California through Monday evening, with the threat of cloud-to-ground lightning, gusty winds and dangerous beach conditions continuing.

On Saturday, many Los Angeles-area beaches were closed due to lightning strikes.

Lightening vs Palm Tree... and the winner is. #CrazyDayInLA pic.twitter.com/cRNCCnG5sY — Linden Ashby (@lindenashby) July 19, 2015

The threat of flash flooding — a leading cause of weather-related deaths in the U.S. — is more significant in the desert Southwest, where storms have been dumping more than 1 inch of rain per hour. This water can quickly turns trickles or tiny streams into raging rapids.

Scary graphic shows California's rain deficit over the 4 year #cadrought! 6.5 feet of rain missing from the Sierras! pic.twitter.com/JfCG9T9HpW — CA Waterkeepers (@CA_Waterkeepers) July 14, 2015

While the rains are at least helping firefighters contain some of the wildfires burning across California, lightning strikes can also spark more fires than the storms will extinguish.

The rains will also do little to lessen the drought's severity, considering that the Golden State needs more than 2 feet of rain to put a meaningful dent in its exceptional drought conditions, with much more needed to replace some of the groundwater that has been pumped out by the agricultural industry.