Tropical Storm "Rosa" approaching Baja California, flooding, debris flows and landslides possible over parts of Mexico and western United States

The center of Tropical Storm "Rosa" was located about 225 km (140 miles) WSW of Punta Eugenia, and 525 km (325 miles) SSW of San Felipe, Mexico at 09:00 UTC on October 1, 2018. Rosa is expected to produce heavy rain across Baja California and northwestern Sonora, Central and Southern Arizona and the rest of the Desert Southwest, Central Rockies and Great Basin. Life-threatening flash flooding is expected as well as dangerous debris flows and landslides in mountainous regions.

The storm had maximum sustained winds of 85 km/h (50 mph) at the time and was moving NW at 19 km/h (12 mph) with minimum central pressure of 994 hPa.

A Tropical Storm Warning is in effect for the west coast of the Baja California peninsula from Punta Abreojos to Cabo San Quintin. A Tropical Storm Watch is in effect for the east coast of Baja California from Bahia de Los Angeles to San Felipe.

On the forecast track, the center of Rosa will approach the central and northern Baja California later today and then move across the peninsula into the northern Gulf of California tonight (PDT). 

Rosa is expected to produce 77 - 153 mm (3 to 6 inches) of rain across Baja California and northwestern Sonora, with isolated 254 mm (10 inches) possible.

Central and Southern Arizona can expect 51 - 102 mm (2 to 4 inches), and isolated totals of 153 mm (6 inches) possible in the mountains of Central Arizona.

The rest of the Desert Southwest, Central Rockies and Great Basin can expect 25 - 77 mm (1 to 2 inches) and isolated totals of 102 mm (4 inches).

These rainfall amounts may produce life-threatening flash flooding, dangerous debris flows and landslides in mountainous regions.

Swells generated by Rosa will affect portions of the coasts of southwestern Mexico, most of the west coast of the Baja California peninsula, and southern California through Tuesday. These swells are likely to cause life-threatening surf and rip current conditions.

Rosa's remnants are expected to move across the Desert Southwest on Tuesday, October 2, producing heavy rain and bringing flash flood conditions to the Desert Southwest, Great Basin, and Central/Southern Rockies through Wednesday. There is a moderate risk of excessive rain in portions of Arizona today and tomorrow.

"Heavy rainfall has made a return to much of Arizona and southeastern California as Tropical Storm 'Rosa' tracks towards the northeast, and it is forecast to make landfall on the northern Baja California coast Monday evening," NWS said early October 1.

"There will be enough deep layer moisture to support widespread 25 - 77 mm (1 to 3 inches) rainfall amounts through Tuesday night, with some additional showers and thunderstorms likely falling thereafter. This moisture will continue spreading inland across eastern Nevada, Utah, and western portions of Colorado and New Mexico." 

Flash flood watches are currently in effect for many of those areas, and the Weather Prediction Center currently has a moderate risk of excessive rainfall for parts of Arizona where the threat of flash flooding is greater.
Bron:https://watchers.news 
 

Likely dangerous flash floods, debris plugs in this area of northern Mexico. Wish I could chase these floods safely after dark but am not familiar with the terrain or road network south of the border #Rosa pic.twitter.com/jXpgBDDohz

— Reed Timmer (@ReedTimmerAccu) 2 oktober 2018

Update: Very heavy rain with #Rosa is inching slowly into far southern AZ. Heavy rain will be starting shortly in the Yuma area, especially east, and Ajo shortly. Will be monitoring washes in the area for flash flood potential tonight @breakingweather pic.twitter.com/6rkrJ0lDED

— Reed Timmer (@ReedTimmerAccu) 2 oktober 2018

Like my headphones after my kid got ahold of them, today's weather comes to you in 3 parts...

1) Tropical moisture from #Rosa overspreads the southwest with several inches possible through Wed. creating dangerous flash flooding, debris flows, and landslides.#TurnAroundDontDrown pic.twitter.com/rF0vSQW8dt

— NWS (@NWS) 1 oktober 2018

Flash flood watches stretch 750 miles from Mexico-Arizona border through Utah. Some locations in Desert Southwest to see up to 4 inches of rain from #Rosa. More info: https://t.co/IlMnHIl0GO pic.twitter.com/U5nnHh3LnN

— Capital Weather Gang (@capitalweather) 1 oktober 2018

Update: morning as-live from Flagstaff AZ ahead of heavy rainfall from #TropicalStormRosa. Plan is to drop south to southern AZ to cover flash flood threat. Stay tuned to @accuweather for updates #azwx pic.twitter.com/Iwv9vT6TyF

— Reed Timmer (@ReedTimmerAccu) 1 oktober 2018

Lightning south of Yucca Valley, CA. #Rosa. @JimCantore @Will_Wilkens @MikeOlbinski pic.twitter.com/aH7JuaFohm

— Ryan Vaccaro (@Rhino40305) 1 oktober 2018

Quick edit of this supercell east of Sunizona earlier today. Had a nice couplet for a bit there before getting all shelfy. Fun day down in far SE AZ. #azwx #rosa pic.twitter.com/XbVtzfa5nF

— Mike Olbinski (@MikeOlbinski) 2 oktober 2018

Update: Canada Del Oro is starting to flow on the west side of Tucson AZ at I10 after a little over an inch estimated on radar upstream. @breakingweather @accuweather #Rosa pic.twitter.com/qOLkzFDXaf

— Reed Timmer (@ReedTimmerAccu) 1 oktober 2018

Wind damage has been reported in Yuma, Arizona ahead of Rosa. Rosa is projected to make landfall on the northern part of Baja California on Monday evening: https://t.co/iHjdSs2nNf https://t.co/j0biZTELox

— AccuWeather (@breakingweather) 30 september 2018

Fortuna wash east of Yuma is raging like a river right now as the first impacts of Hurricane Rosa are being felt. #azwx #Rosa pic.twitter.com/lJ5nB7G97t

— John Sirlin (@SirlinJohn) 30 september 2018

Insane shelf cloud and "Hurriboob" along Interstate 8 west of Gila Bend right now! #azwx #StormHour pic.twitter.com/uXzPjfkvrB

— John Sirlin (@SirlinJohn) 1 oktober 2018

'We're nervous': Mayer Arizona resident preparing for Rosa's rain: ▶ https://t.co/4VZc43a8Pp #TropicalStormRosa

— One News Page (@One_News_Page) 2 oktober 2018

STORY: “When I was your age, we didn’t close school for a little rain.”

However, one school district might adjust the schedule tomorrow, if there are problems with #TropicalStormRosa #FOX10Phoenix https://t.co/1C9acnNhVv

— Matt Rodewald FOX 10 (@Matt_Fox10) 2 oktober 2018

Residents in Scottsdale are stocking up on sandbags, prepping for heavy rain tonight. #TropicalStormRosa #Fox10phoenix pic.twitter.com/oADDC0MEfV

— Jennifer Auh (@JennAuhFOX10) 1 oktober 2018

VIDEO: Drone footage: Hurricane Rosa floods Indian Bend Wash Greenbelt in Scottsdale pic.twitter.com/salNDepRcx

— azcentral (@azcentral) 2 oktober 2018

VIDEO: Rosa storm updates: October rainfall among highest ever for Phoenix https://t.co/UzyBRS91AH via @azcentral pic.twitter.com/3GSux6SnK1

— azcentral (@azcentral) 3 oktober 2018

VIDEO: A timelapse shows the remnants of Hurricane Rosa moving across the Phoenix area. pic.twitter.com/0bXmmSTNMt

— azcentral (@azcentral) 3 oktober 2018

The lingering moisture from Hurricane Rosa may not be finished yet with metropolitan Phoenix. https://t.co/QmAC7850lt

— azcentral (@azcentral) 3 oktober 2018

VIDEO: Hurricane Rosa: Record rainfall continues into evening; flood warning issued for Phoenix area https://t.co/4SnMdbE4IM via @azcentral pic.twitter.com/Jk5b5qM5s2

— azcentral (@azcentral) 3 oktober 2018

Good lord I have never seen this wash flow like this before. #azwx pic.twitter.com/zokp0m1TUe

— Eric Petrone (@azmonsoon) 3 oktober 2018

Flash flood in Fountain Hills. 2 pics taken 12 min apart. #azwx pic.twitter.com/QHQA2ZaO71

— Eric Petrone (@azmonsoon) 3 oktober 2018

A light sprinkle in Fountain Hills. #azwx #Rosa pic.twitter.com/SBFGktdLKZ

— Eric Petrone (@azmonsoon) 3 oktober 2018

This guy is trying not to drown. #azwx pic.twitter.com/eY2Eq6wxtQ

— Eric Petrone (@azmonsoon) 2 oktober 2018

I-17 and Peoria shut down - record rainfall causing flooding all over the valley. #azwx #AZFamily pic.twitter.com/UkTq4fR5d6

— Paul Horton (@PaulHortonCBS5) 2 oktober 2018

Distant storm views from @SaguaroNPS this evening. #azwx #StormHour #monsoon2018 #hurricanerosa pic.twitter.com/mBqSMRM8I0

— Sean Parker (@seanparkerphoto) 3 oktober 2018

A #timelapse video showing some rain falling over Keystone Peak southwest of #tucson during sunset. #azwx pic.twitter.com/P1pLZ1R6if

— Sean Parker (@seanparkerphoto) 3 oktober 2018

Check out one of the most intense rainbows we've ever seen above Phoenix, AZ #azwx Photo: @geraldferguson pic.twitter.com/9cRNlOGNTf

— Chopperguy (@chopperguyhd) 3 oktober 2018