Marine Weather and Tide Forecast for Rillito, AZ

SYNOPSIS

There will be thunderstorm chances each afternoon and evening through the coming week with day to day variability in location and severity, with more widespread chances for showers and thunderstorms forecast Thursday and Friday. Scattered thunderstorms today will bring a threat of heavy rainfall and strong wind gusts. High temperatures will sit just below normal through mid-week before cooling further by the end of the week.

DISCUSSION

Healthy atmospheric moisture will remain across southeastern Arizona today with surface dew points of 55-60 degrees and 1.2-1.6 inches of precipitable water. Impulses aloft continue to push into the region through east/southeast flow, which will trigger scattered thunderstorms across the region again this afternoon. The main hazard today will be heavy rainfall rates and flash flooding, with an isolated strong wind gust threat.
Weak wind shear should preclude an organized thunderstorm wind threat but enough mid- level drying has shown up in forecast soundings to indicate that a strong downburst may accompany any thunderstorm today. Mean wind will begin to turn northeasterly through the day with thunderstorm motions taking on a northeast to southwest to west motion.

The active pattern continues through the week, becoming enhanced during the second half of the week by an incoming easterly wave.
Ensembles are in good agreement with increasing perceptible water overlapping with lowering heights aloft Thursday and Friday, ingredients highlighting an elevated heavy rainfall potential. There remain details to work out regarding instability and rainfall rates, but this period will need to be watched for more widespread impacts. Currently the WPC has Thursday and Friday in a Slight Risk for excessive rainfall across the region.

High temperatures will likely trend down with this incoming easterly wave with forecast highs dipping from around 3 degrees below normal through Wednesday to around 10 degrees below normal on Friday. An extended period of rain and cloud cover during the day may bring even lower highs.

AVIATION
Valid through 15/00Z.

SCT-BKN ceilings 10k-15k through the morning with some diminishing coverage. Scattered thunderstorm redevelopment expected after 14/20Z. Heavy rainfall, mountain obscurations, and erratic strong wind gusts 35-40 kts possible with any thunderstorm. Outside of thunderstorms, surface winds generally light and under 10 kts. Aviation discussion not updated for TAF amendments.

FIRE WEATHER

Daily chances for thunderstorms will continue each afternoon and evening through the coming week with day to day variability. More widespread chances for showers and thunderstorms are possible Thursday and Friday. Minimum relative humidity 25-30 percent in the lower desert locations and above 40 percent in the mountains this week. Winds this week will remain mainly light and under 15 mph, though strong and erratic winds will be possible with any thunderstorm.

TWC WATCHES/WARNINGS/ADVISORIES
None.