For the second consecutve day, upper level disturbances rotating around a large upper level low positioned across California and Nevada contributed to scattered thunderstorms development across portions of the Panhandles. The late afternoon thunderstorms developed across the western to central Texas Panhandle near surface trough and dry line features in the area.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS AMA wrote it up.
For the second consecutve day, upper level disturbances rotating around a large upper level low positioned across California and Nevada contributed to scattered thunderstorms development across portions of the Panhandles. The late afternoon thunderstorms developed across the western to central Texas Panhandle near surface trough and dry line features in the area. A moderately unstable but weakly sheared environment led to strong to severe storms which produced large hail 1-2 in diameter and damaging winds mainly around the south-central Texas Panhandle. The strongest storms clustered around Canynon, Texas where flooding was also observed.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Amarillo, TX wrote its last area forecast discussion before the first event at May 16, 1:58 PM CST, 1 hour 40 minutes earlier.
Area Forecast Discussion National Weather Service Amarillo TX 258 PM CDT Sun May 16 2021 .MESOSCALE UPDATE... ...Severe weather expected today... * Synoptic Overview: Moist west to southwest flow ahead of an upper level trough along with a dryline setup in eastern NM will be the main driver for todays severe storms across the Panhandles. * Mesoscale: A slow progressing upper level trough, along with a surface low in easter NM, and recent rain will help keep the low levels very moist today. Dewpoints are in the upper 50s to lower 60s in Panhandles. Agitated cu fields already showing up in the western Panhandles, suggesting that convection is already trying to take place. Cap almost broken as 19Z AMA sounding shows very little ML CIN. We have decent instability and even some lift as subtle perturbations are expected to move through this evening. We are lacking upper level jet support across the Panhandles to keep storms well organized. * Threats: ML CAPE values 1000-2000 J/kg can be expected with these storms. We do have decent low level shear and helicity values that could result in slightly better hail growth (2.00"), and can't rule out a tornado to be spun up as well. Storms may very well become outflow dominate due the lack of upper level support. And DCAPE values 1000-1500 J/kg would support wind gusts up to 70 mph. This will also cause them to propagate slowly east and thus the heavy rain cores of the storms could linger over certain areas for longer durations. This will lead to an increase flooding threat that needs to be noted. Areas that have received decent amounts of recent rain, will be even more prone to this flood threat. * Timing & Location: The western and central Panhandles will be in the concern for hail up to 2.00" and 70 mph winds, with the eastern Panhandles hail threat slightly lower. Storms expected to move into the western Panhandles from 3-4 PM and progress eastward, where they will eventually start to line out around the Guymon to Amarillo line area, and that should be around 7 PM this evening. The hail threat will begin to decrease thereafter. That being said the increased low level jet around 6-10 PM could enhance the low level spin factor and possibly allow for a brief tornado to spin up. Storms will still be strong to severe as they become more outflow dominate across the eastern Panhandles late this evening and into tonight. There could be some redeveloping overnight convection across the central and southern Panhandles tonight, but storms are only expected to be strong. * Summary: Severe Weather is likely again this evening. While all hazards can't be ruled out, we are focused on the wind and possibly significant hail threat. The tornado threat is very low, but not impossible to occur, and will likely be best around 6-10 PM. Areas that have already received decent rain amounts should be on the lookout for possible flooding issues if prolonged rain occurs again tonight. Weber && .SHORT TERM...Monday and Monday Night... Severe Weather is expected again across the entire Panhandles, with all hazards in play. Upper level trough will approach the four corners region and begin to take a negative tilt, with a shortwave out of the southwest ejected across the Panhandles. Meanwhile, surface low will set up again in eastern NM with a sharp dryline, angled from NE NM down to Lubbock, TX, and dewpoints in the 60s east of the dryline with pretty good easterly flow. ML CAPE values just east of the dryline look to be between 2000-3000 J/kg, and thus there will be plenty of instability. The closer proximity of the upper level trough will also aid in strong winds aloft across the southern Panhandles. So with high dewpoints east of the dryline, ample shear aloft, and decent low level helicity values, it appears favorable for all hazards. In collaboration with SPC, the hail and wind threat has been increased to 30 percent with the southern Panhandles hatched for greater than 2" hail. Areas in the central and northern Panhandles don't quite have as good upper level support, but that doesn't remove them from the severe weather threat. The tornado threat has been increased to 5 percent from Amarillo east as this is likely the area between 4 and 7 pm that storms could develop and have all the ingredients needed for tornadoes. After 7 pm, expect that threat to decrease as the upper level winds will shift out of southeast, instead of southwest, and decent backing will occur aloft. This could cause issue with the storms holding together. In general, all areas are expected to see storms, with a decent chance for severe weather. However, the best favored area will be to the south and southeast Panhandles. Keep in mind with the past several days of rainfall across the area, that any continued rain will likely increase the flood threat. One last thing to note is, while most models don't suggest this, there's a small chance that the surface low tracks east into the southwest Panhandles before convection occurs. This would bring in much drier air and shut down any severe weather threat. However, this same area could be in a pretty favorable position for severe weather if the dryline holds to eastern NM, as we suspect. So Deaf Smith and Oldham County may be in that all or nothing area, that's contingent on the progression of the dryline. Weber && .LONG TERM...Tuesday through Saturday... An active weather pattern of persistent precipitation chances will continue through much of the long term forecast period. Starting on Tuesday, latest 16/12Z model and numerical data shows the main H500 low moves east across the CO/NM border throughout the day. As it does so, large scale H500-300 UL divergence will take place across the Panhandles region with a second jet streak developing across central Oklahoma as light and variable H500 flow encompasses the southeast CONUS. In-conjunction with afternoon lee troughing and sfc based dryline tightening, strong to severe thunderstorms once again will be possible. Mid range model data is not in an accord on where exactly the dryline will set up with model outputs ranging from west to east across the Panhandles. Highest probs will be across the central and eastern Panhandles where also more time for the environment to recover will take place. Low level theta-e advection will also be ramping up across the eastern Panhandles which will assist in lowering LCL and aiding in the MUCAPE of 1000-2000 J/kg. Shear will increase going further into Tuesday night as a LLJ develops, but enough shear during the afternoon hours, with near orthogonal flow to the dryline will suffice for supercells with all hazards potentially in play. Some factors to watch that may hinder thunderstorm development could be recovery time from previous day of thunderstorms along with a prolonged cap that may hinder surface based convection. Tuesday would be one to watch closely. Latest 16/12Z model and numerical guidance is hinting at some agreement Wednesday through Saturday. Latest guidance continues to build a large domain anti-cyclonic feature across the southeast CONUS and Ohio Valley. In-conjunction, a very notable upper level low pressure becomes cut off from the northern jet and drifts into the Great Basin by Saturday. As a result, the aforementioned upper level low pressure will open into a wave and slowly move north into the central Plains before getting absorbed back into the northern stream jet. As a result, continued rounds of showers and storms are possible for the Panhandles as Gulf of Mexico moisture transport streams north into portions of the central Plains. Some factors this far out is difficult to pinpoint if storms could be strong or severe at this time, but will update accordingly as we get closer with time. Temperatures throughout the long term forecast period will be at to above average. Meccariello && .AVIATION...18Z TAFS... VFR conditions likely for the next 6 hours with minimal impacts to the terminals before 00z. There is a chance that storms pop up near or around the terminals before 00z, but will note with Amendments if that looks to be so. After 00z there's a good chance all terminals will be impacted by storms for at least a 2-4 hour period as slow moving storms are expected. Possible 2nd round of storms behind the main line overnight tonight covered with PROB30s at KAMA and KDHT. After storms clear, the TAF sites should go quiet again but convection expected again after 18z Monday at all TAF sites. Expect greater thunderstorm detail in the 00z TAFs (0-6z timeframe) as we will have a better idea of TSRA timing. Winds will generally be out of the south and east approx 10kts for the TAF period. Weber && .PRELIMINARY POINT TEMPS/POPS... Amarillo TX 56 79 54 77 54 / 90 20 50 40 20 Beaver OK 57 77 54 76 55 / 90 50 70 60 50 Boise City OK 50 73 49 71 48 / 90 50 70 60 30 Borger TX 59 82 57 80 57 / 90 20 60 50 30 Boys Ranch TX 55 81 52 79 53 / 90 40 50 40 20 Canyon TX 55 81 52 78 53 / 90 20 40 40 20 Clarendon TX 58 78 57 76 57 / 90 30 50 50 30 Dalhart TX 50 76 47 74 48 / 90 50 60 50 30 Guymon OK 55 76 52 76 53 / 90 50 70 50 40 Hereford TX 54 82 52 80 52 / 90 30 30 40 20 Lipscomb TX 57 78 56 76 56 / 90 40 70 60 50 Pampa TX 57 78 55 75 56 / 90 30 60 50 30 Shamrock TX 58 79 57 76 57 / 90 40 70 60 40 Wellington TX 59 81 59 77 58 / 90 40 60 60 40 && .AMA Watches/Warnings/Advisories... TX...None. OK...None. && 89/89/29/89
Hazardous Weather Outlook...UPDATED National Weather Service Amarillo TX 352 PM CDT Sun May 16 2021 OKZ001>003-TXZ001>020-317-170900- Cimarron-Texas-Beaver-Dallam-Sherman-Hansford-Ochiltree-Lipscomb- Hartley-Moore-Hutchinson-Roberts-Hemphill-Oldham-Potter-Carson- Gray-Wheeler-Deaf Smith-Randall-Armstrong-Donley-Collingsworth- Palo Duro Canyon- 352 PM CDT Sun May 16 2021 This Hazardous Weather Outlook is for the Texas and Oklahoma Panhandles. .DAY ONE...This Afternoon and Tonight. A Severe Thunderstorm Watch is in effect through 11 PM CDT for the Texas Panhandle except Lipscomb County and Oklahoma Panhandle except Beaver County. The strongest storms could be severe and be capable of producing hail up to 2 inches in diameter and 70 mph wind gusts. Heavy rainfall due to slow storm motions could bring localized flooding. In addition, a tornado cannot be ruled out though the threat is low. .DAYS TWO THROUGH SEVEN...Monday through Saturday. Thunderstorms may develop across portions of the Texas and Oklahoma Panhandles Monday through Saturday. Thunderstorms may reach severe levels, especially on Monday. Large to very large hail and damaging winds are the mains threats. There is also a tornado threat late Monday afternoon into early Monday evening. .SPOTTER INFORMATION STATEMENT... Spotter activation is requested through 11 PM CDT this evening. Spotter activation may be needed Monday and Tuesday. Bieda
Special Weather Statement National Weather Service Amarillo TX 425 PM CDT Sun May 16 2021 TXZ007-012-162200- Potter TX-Moore TX- 425 PM CDT Sun May 16 2021 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN POTTER AND SOUTH CENTRAL MOORE COUNTIES UNTIL 500 PM CDT... At 425 PM CDT, Doppler radar was tracking a strong thunderstorm 4 miles northeast of Valley De Oro, or 23 miles northwest of Amarillo, moving northeast at 10 mph. Nickel size hail and wind gusts up to 50 mph will be possible with this storm. This storm will remain over mainly rural areas of northwestern Potter and south central Moore Counties. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take shelter in a sturdy building if threatening weather approaches. && LAT...LON 3542 10203 3550 10214 3567 10202 3552 10178 TIME...MOT...LOC 2125Z 224DEG 10KT 3549 10205 Rutt
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE AMARILLO TX
438 PM CDT SUN MAY 16 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0438 PM HAIL 4 SSW AMARILLO 35.15N 101.85W
05/16/2021 M1.00 INCH RANDALL TX PUBLIC
&&
BIEDAThe Amarillo radar (KAMA), 19 km away, was scanning. The volume nearest the first event began at 21:38 UTC.
15 hail, 1 flood, 1 thunderstorm wind, 1 flash flood. Local standard time, as filed.
Multiple reports came in between 1538 CST and 1623 CST around south and southwest Amarillo. These reports came from the public, trained spotters, and even NWS employees. The hail sizes range from 1 inch to 2 inches.
Multiple reports came in from 1550 CST to 1612 CST for hail sizes ranging from 0.75 to 1.25 around southern Amarillo or west to northwest of Timbercreek Canyon. Sources for the reports ranged from public to emergency managers to spotters.
From 1711 CST to 1715 CST multiple reports came in for large hail ranging from 1 to 2 located in Canyon to just northeast of Canyon. Report sources ranged from public to spotters, with a report from an NWS employee as well.
Reports received of curb to curb flooding.
Right around 1730 CST two reports were made for 1 hail around northeast Amarillo. One of which was an official NWS observation at WFO AMA.
From 1737 CST to 1744 CST multiple reports of large hail ranging from 1 to 1.75 were made for areas around Cayon to the norhwest through parts of town and ending east of Canyon. Report sources included public and trained spotters.
Downed powerlines were reported at 23rd St. and 10th Ave in Canyon.
From 1747 CST to 1802 CST, multiple reports of large hail ranging from 0.75 to 1.75 came in for an area just south of Vega along HWY 385. Report sources include public and trained spotters.
Around 1756 CST to 1757 CST two reports of hail larger than 1 were made around east Canyon to just south of Amarillo along the I-27 corridor. One report was for 2 hail made by an NWS employee located 3 miles east of Canyon.
Fire officials reported stranded vehicles and flooded roads along I-27 and HWY 217. Several other reports came in from the public of stranded vehicles as well.
Accumulating hail between pea and dime size, with larger stones up to ping pong ball noted. Area roadway is covered with hail.
Once again portions of Canyon especially eastern to northern portions received large hail, this time maxing out at 1.5.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Texas in 2021Every state in 2021This day in weather historyWarnings in Texas, May 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 952392, 952394, 952393, 952395, 952422, 952398, 952396, 952425, 952397, 952399, 952418, 952415, 952414, 952400, 952412, 952401, 952403, 952402.