sweetapricity/bridgedeck-noaa huggingface dataset:
The remnants of Hurricane Harvey moved across the ArkLaMiss region on August 30th and 31st and brought gusty winds and rain to the region. As Harvey decreased to a depression on the 31st, gusty winds still remained across portions of the region. This resulted in some downed trees outside of any shower activity. Locally heavy rainfall resulted in instances of flash flooding.

Strong Wind in ASHLEY, ARKANSAS
From 31-AUG-17 05:30:00 to 31-AUG-17 05:30:00 (CST-6)
Magnitude: 43.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Public

A large pine tree was blown down across Ashley County Road 12 just east of the county landfill around Hamburg.

Flood in CHICOT, ARKANSAS
From 31-AUG-17 11:15:00 to 31-AUG-17 13:15:00 (CST-6)
Location: DERMOTT
Flood cause: Heavy Rain
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Social Media

Minor street flooding occurred on Gibson Circle.
There was an isolated report of flooding.

Flash Flood in NEWTON, MISSOURI
From 11-AUG-17 06:30:00 to 11-AUG-17 08:30:00 (CST-6)
Location: NEOSHO
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Several roads were closed in Neosho due to flooding.
Tropical Storm Harvey emerged back over the Northwest Gulf of Mexico during the morning hours of August 28th, and intensified slightly as drifted northwest just off the Southeast Texas coast, eventually making a 3rd landfall near Cameron, Louisiana during the early morning hours of August 30th. The persistent outer bands of Tropical Storm Harvey began consistently affecting Angelina, Nacogdoches, San Augustine, and Sabine Counties throughout the day on August 30th, resulting in reports of downed trees and power lines as some of the stronger squalls produced wind gusts to 35-40 mph with locally higher gusts atop already saturated grounds.
In Angelina County, trees were blown down on FM 1818 near Biloxi Creek about 5 miles east southeast of Diboll. In Nacogdoches County, power lines were blown down across FM 2259, 3 miles southeast of Highway 224 just southeast of Nacogdoches. A tree also fell across both lanes of FM 95 about 4 miles south of Martinsville. In San Augustine County, several trees and power lines were blown down in Broaddus. In Sabine County, a tree fell on FM 2024 just east of Bronson, causing a vehicle to crash. There were unknown injuries. In addition, trees were blown down across Highway 87 at Redhill Lake, Odis Lowe Road, and FM 1592 about 1 mile north of Highway 184 in Northern Sabine County.

Tropical Storm in ANGELINA, TEXAS
From 30-AUG-17 02:50:00 to 30-AUG-17 18:45:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Tropical Storm in NACOGDOCHES, TEXAS
From 30-AUG-17 02:50:00 to 30-AUG-17 18:45:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Tropical Storm in SAN AUGUSTINE, TEXAS
From 30-AUG-17 02:50:00 to 30-AUG-17 18:45:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Tropical Storm in SABINE, TEXAS
From 30-AUG-17 02:50:00 to 30-AUG-17 18:45:00 (CST-6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement
Isolated afternoon and evening thunderstorms created minor flooding in Montgomery County, Maryland during the evening of August 1st.

Flood in MONTGOMERY, MARYLAND
From 01-AUG-17 17:31:00 to 01-AUG-17 20:00:00 (EST-5)
Location: TAKOMA PARK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Several inches of water were flowing down walkways and the roadway surface on Piney Branch Road near Manchester Road.
A cold front and an unstable atmosphere led to some severe thunderstorms.

Hail in MORGAN, WEST VIRGINIA
From 12-AUG-17 14:50:00 to 12-AUG-17 14:50:00 (EST-5)
Location: BERKELEY SPGS
Magnitude: 1.00 
Reported by: Trained Spotter

Quarter sized hail was reported.

Hail in BERKELEY, WEST VIRGINIA
From 12-AUG-17 15:05:00 to 12-AUG-17 15:05:00 (EST-5)
Location: JOHNSTOWN
Magnitude: 1.00 
Reported by: Trained Spotter

Dime to quarter sized hail was reported.

Thunderstorm Wind in MORGAN, WEST VIRGINIA
From 12-AUG-17 14:40:00 to 12-AUG-17 14:40:00 (EST-5)
Location: BERKELEY SPGS
Magnitude: 50.00 EG
Reported by: Trained Spotter

A tree fell onto power lines along Wild Turkey Road.

Thunderstorm Wind in MORGAN, WEST VIRGINIA
From 12-AUG-17 14:43:00 to 12-AUG-17 14:43:00 (EST-5)
Location: GREAT CACAPON
Magnitude: 50.00 EG
Reported by: Trained Spotter

A tree fell onto a car near Panorama at the peak.

Thunderstorm Wind in MORGAN, WEST VIRGINIA
From 12-AUG-17 14:44:00 to 12-AUG-17 14:44:00 (EST-5)
Location: RIDERSVILLE
Magnitude: 50.00 EG
Reported by: 911 Call Center

Power lines were down near the intersection of Hope Road and Guitar Lane.

Thunderstorm Wind in MORGAN, WEST VIRGINIA
From 12-AUG-17 14:44:00 to 12-AUG-17 14:44:00 (EST-5)
Location: BERKELEY SPGS
Magnitude: 50.00 EG
Reported by: Trained Spotter

Multiple trees were down across Route 9 near the intersection of Quaint Acres Lane.

Thunderstorm Wind in MORGAN, WEST VIRGINIA
From 12-AUG-17 14:46:00 to 12-AUG-17 14:46:00 (EST-5)
Location: BERKELEY SPGS
Magnitude: 50.00 EG
Reported by: Trained Spotter

Nine locust trees approximately 12 to 14 inches in diameter were snapped halfway up.

Thunderstorm Wind in MORGAN, WEST VIRGINIA
From 12-AUG-17 14:49:00 to 12-AUG-17 14:49:00 (EST-5)
Location: NEW HOPE
Magnitude: 50.00 EG
Reported by: Public

Several large trees were down along Spohrs Road between the intersection of New Hope Road and Eckerd Lane.

Thunderstorm Wind in MORGAN, WEST VIRGINIA
From 12-AUG-17 14:56:00 to 12-AUG-17 14:56:00 (EST-5)
Location: HOLTON
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree was down on Victory Lane.

Thunderstorm Wind in JEFFERSON, WEST VIRGINIA
From 12-AUG-17 17:13:00 to 12-AUG-17 17:13:00 (EST-5)
Location: MANNINGS
Magnitude: 50.00 EG
Reported by: 911 Call Center

A tree fell into a house along Stone Ridge Road.
Conditions were very dry when a dry lightning event started the Jones Fire in the Willamette National Forest, in the Little Fall Creek watershed.

Wildfire in CASCADE FOOTHILLS IN LANE COUNTY, OREGON
From 10-AUG-17 17:51:00 to 31-AUG-17 23:59:00 (PST-8)
Reported by: Park/Forest Service

Conditions were very dry when a dry lightning event started the Jones Fire in the Willamette National Forest, in the Little Fall Creek watershed. By the end, the Jones Fire had burned around 10,500 acres.
Dry conditions preceded a dry lightning event, which started the Staley Fire in the Willamette National Forest, 23 miles south of Oakridge, OR.

Wildfire in CASCADES IN LANE COUNTY, OREGON
From 09-AUG-17 20:00:00 to 31-AUG-17 23:59:00 (PST-8)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Dry conditions preceded a dry lightning event, which started the Staley Fire in the Willamette National Forest, 23 miles south of Oakridge, OR.  By the end, it had burned around 2300 acres.
Isolated severe thunderstorms developed as an east-west cold front moved south and encountered a more unstable air mass with marginal deep layer shear. The storms produced mainly hail up to an inch in diameter.

Hail in OUTAGAMIE, WISCONSIN
From 30-AUG-17 14:09:00 to 30-AUG-17 14:09:00 (CST-6)
Location: SCHIOCTON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Quarter size hail fell and covered the ground north of Shiocton. Winds from the storm also broke tree branches of up to 8 inches in diameter.

Hail in OUTAGAMIE, WISCONSIN
From 30-AUG-17 14:52:00 to 30-AUG-17 14:52:00 (CST-6)
Location: APPLETON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Hail, up to quarter size, fell in Grand Chute.
A strong cold front moved across central North Carolina during the evening into the overnight hours. Showers and storms developed in advance of the front along a prefrontal trough. Some of these storms became severe across eastern portions of central North Carolina, producing wind damage. One such report of damage resulted in an individual being injured from a large tree branch falling on a car, trapping and injuring the occupant.

Hail in NASH, NORTH CAROLINA
From 23-AUG-17 15:25:00 to 23-AUG-17 15:25:00 (EST-5)
Location: CASTALIA
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Nickel size hail was reported on Race Track Road.

Thunderstorm Wind in WAKE, NORTH CAROLINA
From 23-AUG-17 14:53:00 to 23-AUG-17 14:58:00 (EST-5)
Location: LASSITER
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Trees were reported down near Rolesville and Zebulon.

Thunderstorm Wind in JOHNSTON, NORTH CAROLINA
From 23-AUG-17 16:50:00 to 23-AUG-17 16:50:00 (EST-5)
Location: SMITHFIELD
Magnitude: 50.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Public

Billboards were damaged and trees were reported down near the Brogden Road exit along Interstate 95.

Thunderstorm Wind in JOHNSTON, NORTH CAROLINA
From 23-AUG-17 16:52:00 to 23-AUG-17 16:52:00 (EST-5)
Location: SMITHFIELD
Magnitude: 50.00 EG
Property damage: 10.00K
Crop damage: 0.00K
Reported by: 911 Call Center

A large tree branch fell on a car on Lee Street. An entrapped occupant sustained minor injuries.

Thunderstorm Wind in JOHNSTON, NORTH CAROLINA
From 23-AUG-17 16:54:00 to 23-AUG-17 16:54:00 (EST-5)
Location: SMITHFIELD
Magnitude: 50.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Damage was reported at a few auto sales stores on Brightleaf Boulevard, between Brogden Road and 5th Street.

Thunderstorm Wind in JOHNSTON, NORTH CAROLINA
From 23-AUG-17 16:54:00 to 23-AUG-17 16:54:00 (EST-5)
Location: SMITHFIELD
Magnitude: 50.00 EG
Property damage: 100.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Multiple trees and power lines were reported down, along with structural damage to multiple buildings and carports in Smithfield.

Thunderstorm Wind in SAMPSON, NORTH CAROLINA
From 23-AUG-17 18:55:00 to 23-AUG-17 18:55:00 (EST-5)
Location: INGOLD
Magnitude: 50.00 EG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Department of Highways

Multiple trees were reported down on Ebenezer Forest Road.
A line of showers and thunderstorms associated with a short wave aloft moved through Central North Carolina in a moderately unstable environment. One storm produced a downburst, resulting in isolated wind damage.

Thunderstorm Wind in FRANKLIN, NORTH CAROLINA
From 17-AUG-17 15:30:00 to 17-AUG-17 15:30:00 (EST-5)
Location: LOUISBURG
Magnitude: 50.00 EG
Property damage: 3.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Several trees and a few large tree limbs were blown down along a swath through downtown Louisburg.
Northwest flow aloft persisted this day, and weak disturbances tracked over the region. Instability increased as a cold front sunk into the CWA.  In addition, the airmass over the central Plains continued to be fairly moist. This was enough lift and instability to produce a thunderstorm in Barber county with 4.25 in hail and 70 mph winds.

Thunderstorm Wind in BARBER, KANSAS
From 09-AUG-17 18:37:00 to 09-AUG-17 18:37:00 (CST-6)
Location: KIOWA ARPT
Magnitude: 61.00 EG
Reported by: Public

There was also giant hail reported in the area.

Hail in BARBER, KANSAS
From 09-AUG-17 17:57:00 to 09-AUG-17 17:57:00 (CST-6)
Location: MEDICINE LODGE
Magnitude: 4.25 
Reported by: Law Enforcement
A mid-level disturbance moved across Southern New England, tapping very moist and unstable air to create showers and thunderstorms.  Some showers and storms produced heavy downpours and strong wind gusts.

Thunderstorm Wind in PROVIDENCE, RHODE ISLAND
From 02-AUG-17 12:35:00 to 02-AUG-17 12:35:00 (EST-5)
Location: SLATERSVILLE
Magnitude: 50.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Amateur Radio

At 1235 PM EST, a tree was brought down in North Smithfield on Providence Pike at Industrial Drive.
In the unstable air ahead of a strong cold front, showers and thunderstorms formed across the middle Ohio River Valley on the morning 4th. Most of the storms were just general summer time thunderstorms, however one did pulse up and produce some wind damage.

Thunderstorm Wind in WASHINGTON, OHIO
From 04-AUG-17 11:19:00 to 04-AUG-17 11:19:00 (EST-5)
Location: RENO
Magnitude: 50.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Multiple trees were uprooted in Reno.
Stacked high pressure was over the region with a moist airmass and unstable diurnal conditions. Heavy rainfall occurred in slow moving cells.

Heavy Rain in MARION, FLORIDA
From 07-AUG-17 18:05:00 to 07-AUG-17 18:50:00 (EST-5)
Location: OCALA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter estimated 2-2.25 inches within 45 minutes.

Heavy Rain in MARION, FLORIDA
From 06-AUG-17 23:00:00 to 07-AUG-17 19:45:00 (EST-5)
Location: BELLEVIEW
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A spotter measured 2.75 inches in a short period of time.
With an upper trough in the area acting on abundant low-level tropical moisture, heavy showers and thunderstorms developed from the Big Island to Kauai.  Most of the rain caused ponding on roadways, and small stream and drainage ditch flooding.  On Kauai, the soaking precipitation produced flash flooding as Kuhio Highway in Hanalei became impassable, and county officials were forced to close the Hanalei Bridge.  There were no reports of significant property damage or injuries.

Heavy Rain in HAWAII, HAWAII
From 20-AUG-17 13:28:00 to 20-AUG-17 20:48:00 (HST-10)
Location: PEPEEKEO
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Lightning in KAUAI, HAWAII
From 20-AUG-17 22:24:00 to 20-AUG-17 22:24:00 (HST-10)
Location: KALIHIWAI
Property damage: 10.00K
Crop damage: 0.00K
Reported by: 911 Call Center

Power outage in Kilauea after a transformer was struck by lightning.

Flash Flood in KAUAI, HAWAII
From 21-AUG-17 01:00:00 to 21-AUG-17 05:00:00 (HST-10)
Location: PRINCEVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Kuhio Highway near the Hanalei Bridge was closed because of flooding waters on the roadway.

Heavy Rain in HONOLULU, HAWAII
From 21-AUG-17 10:07:00 to 21-AUG-17 14:15:00 (HST-10)
Location: PUNALUU
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in HAWAII, HAWAII
From 21-AUG-17 13:41:00 to 21-AUG-17 17:18:00 (HST-10)
Location: VOLCANO
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Heavy Rain in MAUI, HAWAII
From 21-AUG-17 13:53:00 to 21-AUG-17 17:17:00 (HST-10)
Location: MALA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Official NWS Observations

Flash Flood in KAUAI, HAWAII
From 21-AUG-17 15:57:00 to 21-AUG-17 22:43:00 (HST-10)
Location: WAILUA HOMESTEADS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Loop Road low water crossings became inundated near the Wailua River. Also, Kuhio Highway near the Hanalei Bridge was closed for a time because of water over the roadway.
Thunderstorms developed across the eastern portions of the greater Phoenix area during the late afternoon hours on August 26th, and a few of these storms produced locally heavy rains which led to an episode of flash flooding east of Phoenix and in the area around Apache Junction. Rainfall east of Phoenix was not extreme, but at least one weather spotter measured nearly three quarters of an inch within 20 minutes, and due to rapidly responding streams and washes in the area, this was enough to produce flash flooding. At 1820MST flash flooding swept 2 cars down a wash and 2 drivers had to be rescued. This occurred about 4 miles southeast of Apache Junction. A Flash Flood Warning was in effect at the time of the water rescues. Fortunately no injuries were reported.

Flash Flood in PINAL, ARIZONA
From 26-AUG-17 17:45:00 to 26-AUG-17 20:30:00 (MST-7)
Location: PALM SPGS
Flood cause: Heavy Rain
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Thunderstorms with locally heavy rains developed across the eastern portion of the greater Phoenix area during the late afternoon hours on August 26th, and some of the stronger storms affected the community of Apache Junction. The storms produced some intense rainfall; a trained spotter located 2 miles southeast of Apache Junction measured about 0.74 inches of rain within 20 minutes near the intersection of Tomahawk Road and the Superstition Freeway; this suggested a rain rate around 2 inches per hour. Rain of this magnitude was more than enough to cause flash flooding in Apache Junction given the rapid response nature of streams and washes, such as Weekes Wash, in the area. As washes began to rapidly fill and flow they began to pose an extreme hazard to area motorists. At 1820MST local broadcast media reported that 2 drivers needed to be rescued by bystanders from 2 cars that were both swept down a a wash, eventually becoming lodged underneath a foot bridge. The location of the rescue was near the intersection of Southern Avenue and Mountain View Road, about 4 miles southeast of Apache Junction. Fortunately there were no reports of serious injuries to either driver. A Flash Flood Warning was in effect at the time of the flooding; it was issued at 1734MST and it was in effect through 2030MST.
Isolated severe thunderstorms formed along lake breeze boundaries over portions of central Upper Michigan on the afternoon of the 1st.

Hail in DELTA, MICHIGAN
From 01-AUG-17 12:22:00 to 01-AUG-17 12:26:00 (EST-5)
Location: PERKINS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Delayed report from MPING of one inch diameter hail near Perkins.

Thunderstorm Wind in ALGER, MICHIGAN
From 01-AUG-17 16:00:00 to 01-AUG-17 16:06:00 (EST-5)
Location: ONOLA
Magnitude: 70.00 EG
Property damage: 70.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Over 100 12-24 inch diameter trees were snapped and uprooted five miles west-northwest of Au Train.  Two trees were down on a house along Rock River Road.  Power lines were also reported down.
Late this afternoon, a pulse thunderstorm drifted south along the Lubbock and Hockley County line. A series of traveling downbursts accompanied this storm from Reese Center south to extreme southwest Lubbock County, along with torrential rainfall rates of up to 0.42 inches in just five minutes.

Heavy Rain in LUBBOCK, TEXAS
From 07-AUG-17 17:45:00 to 07-AUG-17 18:05:00 (CST-6)
Location: WOLFFORTH
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

A Texas Tech University West Texas mesonet southwest of Wolfforth measured 1.54 inches of rain in 20 minutes; 0.42 inches of which fell in just five minutes.

Thunderstorm Wind in LUBBOCK, TEXAS
From 07-AUG-17 17:25:00 to 07-AUG-17 17:53:00 (CST-6)
Location: (REE)REESE AFB LUBBO
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Measured by a Texas Tech University West Texas mesonet at Reese Center. This same storm continued moving south and produced similar winds at a NWS employee's home south of Wolfforth.
Isolated strong thunderstorms developed during the heat of the afternoon in a weakly sheared environment. A broad area of weak low pressure over eastern Missouri and western Illinois provided enough convergence for storms to form. A weak 500 mb impulse embedded in a light northwest flow aloft contributed to convective development. A waterspout occurred over Rend Lake, and dime-size hail fell at Carbondale.

Tornado in JEFFERSON, ILLINOIS
From 02-AUG-17 17:27:00 to 02-AUG-17 17:29:00 (CST-6)
Location: INA
Tornado F-scale: EF0
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A waterspout was photographed over northern Rend Lake between Nason and Ina. The upper portion of the waterspout was not visible in the photo. The lower portion was a narrow, cylindrical column that produced spray where it contacted the lake surface. The waterspout was also reported by an emergency management official.  The waterspout was associated with a thunderstorm that produced heavy rain and possibly some small hail.

Hail in JACKSON, ILLINOIS
From 02-AUG-17 12:49:00 to 02-AUG-17 12:49:00 (CST-6)
Location: CARBONDALE
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter
An upper trough dropped southward over California from the evening of the 13th through the early morning of the 15th producing strong down slope west to northwest winds over the Kern County Mountains and Deserts as pressure gradients increased over the area.

High Wind in SE KERN CTY DESERT, CALIFORNIA
From 13-AUG-17 22:40:00 to 13-AUG-17 22:40:00 (PST-8)
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

The APRS station 1NNW Mojave reported a maximum wind gust of 58 mph.

High Wind in KERN CTY MTNS, CALIFORNIA
From 14-AUG-17 14:27:00 to 14-AUG-17 14:27:00 (PST-8)
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

The Bird Springs Pass RAWS reported a maximum wind gust of 58 mph.

High Wind in INDIAN WELLS VLY, CALIFORNIA
From 14-AUG-17 22:26:00 to 14-AUG-17 22:26:00 (PST-8)
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

The Indian Wells Canyon RAWS reported a maximum wind gust of 58 mph.

High Wind in KERN CTY MTNS, CALIFORNIA
From 14-AUG-17 22:32:00 to 14-AUG-17 22:32:00 (PST-8)
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: RAWS

The Blue Max RAWS reported a maximum wind gust of 60 mph.
A persistent low pressure system off the Southern California Coast produced enough instability for thunderstorms to develop over the Southern Sierra Nevada each afternoon between August 17 and August 23.  On the afternoon of the 18th, some slow moving thunderstorms produced heavy rainfall over Yosemite National Park which resulted in flash flooding in Yosemite Valley.

Heavy Rain in MARIPOSA, CALIFORNIA
From 18-AUG-17 15:45:00 to 18-AUG-17 16:45:00 (PST-8)
Location: YOSEMITE VLG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

A slow moving thunderstorm produced 1.27 inches of rainfall in one hour at Yosemite Valley. Pea sized hail was also reported.

Flash Flood in MARIPOSA, CALIFORNIA
From 18-AUG-17 16:15:00 to 18-AUG-17 17:15:00 (PST-8)
Location: YOSEMITE VLG
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

Park Service video showed flash flooding in Yosemite Valley from heavy rainfall.