Alert archive / New York / Flash Flood Watches in 2021

Flash Flood Watch 2, NWS Buffalo, NY

July 16, 202114 counties in New York

NWS Buffalo, NY issued this flash flood watch at Jul 16, 2021, 2:41 PM EDT for 14 counties in New York. It took effect at Jul 16, 2021, 11:00 PM EDT. It was in force for 23 hr.

The area

The counties it named.

The facts

Issued
Jul 16, 2021, 2:41 PM EDT (18:41 UTC)
In effect from
Jul 16, 2021, 11:00 PM EDT
Expired
Jul 17, 2021, 10:27 PM EDT
In force
23 hr
Issued by
NWS Buffalo, NY
Flood severity
None

Counties Allegany County, NY, Cattaraugus County, NY, Cayuga County, NY, Chautauqua County, NY, Erie County, NY, Genesee County, NY, Livingston County, NY, Monroe County, NY, Niagara County, NY, Ontario County, NY, Orleans County, NY, Oswego County, NY, Wayne County, NY, Wyoming County, NY

The radar

The Buffalo radar (KBUF), 69 km from the middle of the area, began a volume at 18:44 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Buffalo Intl Airport, NY (KBUF), launched 12:00Z, 6.7 hours before the alert went out and 65 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Buffalo Intl Airport, NY at 12:00Z on 2021-07-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Buffalo Intl Airport, NY at 12:00Z on 2021-07-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 45 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1011 m above ground
0-6 km bulk shear
48 kt
0-1 km storm-relative helicity
45 m²/s²
0-3 km storm-relative helicity
117 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

094 
WGUS61 KBUF 161841
FFABUF

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Buffalo NY
241 PM EDT Fri Jul 16 2021

NYZ001>006-010>013-019>021-085-170245-
/O.NEW.KBUF.FF.A.0002.210717T0300Z-210718T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Northern Erie-
Genesee-Wyoming-Livingston-Chautauqua-Cattaraugus-Allegany-Southern
Erie-
Including the cities of Orchard Park, Rochester, Geneseo, Buffalo, 
Oswego, Batavia, Medina, Newark, Olean, Wellsville, Springville, 
Fair Haven, Jamestown, Niagara Falls, and Warsaw
241 PM EDT Fri Jul 16 2021

...FLASH FLOOD WATCH IN EFFECT FROM 11 PM EDT THIS EVENING THROUGH 
LATE SATURDAY NIGHT...

The National Weather Service in Buffalo has issued a

* Flash Flood Watch for portions of central and western New York, 
  including the following counties, in central New York, Northern 
  Cayuga and Oswego. In western New York, Allegany, Cattaraugus, 
  Chautauqua, Genesee, Livingston, Monroe, Niagara, Northern Erie, 
  Orleans, Southern Erie, Wayne and Wyoming.

* From 11 PM EDT this evening through late Saturday night.

* An area of low pressure will track northeast across Ohio tonight 
  along a stationary front that stretches all the way east through 
  western and central New York. This area of low pressure will then 
  track east across western NY and the Finger Lakes region on 
  Saturday. Moderate to heavy rain will enter far western NY tonight 
  and then track eastward across the region through Saturday evening. 
  Thunderstorms are possible and due to recent substantial rainfall, 
  localized flooding is a concern. One hour flash flood guidance is 1 
  to 2 inches across a majority of the region. This could easily be 
  reached, especially if training thunderstorms or organized areas of 
  slow moving heavy rain occur near Metro areas and locations prone to 
  flooding. Rises on rivers and creeks are also expected. However, the 
  rivers and creeks of most concern at this time are the Buffalo 
  Creeks, where minor to even some moderate flooding may occur due to 
  an additional 2 to 2.5 inches of rainfall that is expected by 
  Saturday afternoon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

JM
6 follow-up statements
455 
WGUS61 KBUF 161918
FFABUF

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Buffalo NY
318 PM EDT Fri Jul 16 2021

NYZ014-170330-
/O.EXA.KBUF.FF.A.0002.210717T0300Z-210718T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Ontario-
Including the cities of Canandaigua
318 PM EDT Fri Jul 16 2021

...FLASH FLOOD WATCH IN EFFECT FROM 11 PM EDT THIS EVENING THROUGH 
LATE SATURDAY NIGHT...

The National Weather Service in Buffalo has expanded the

* Flash Flood Watch to include a portion of western New York, 
  including the following county, Ontario.

* From 11 PM EDT this evening through late Saturday night.

* An area of low pressure will track northeast across Ohio tonight 
  along a stationary front that stretches all the way east through 
  western and central New York. This area of low pressure will then 
  track east across western NY and the Finger Lakes region on 
  Saturday. Moderate to heavy rain will enter far western NY tonight 
  and then track eastward across the region through Saturday evening. 
  Thunderstorms are possible and due to recent substantial rainfall, 
  localized flooding is a concern. One hour flash flood guidance is 1 
  to 2 inches across a majority of the region. This could easily be 
  reached, especially if training thunderstorms or organized areas of 
  slow moving heavy rain occur near Metro areas and locations prone to 
  flooding. Rises on rivers and creeks are also expected. However, the 
  rivers and creeks of most concern at this time are the Buffalo 
  Creeks, where minor to even some moderate flooding may occur due to 
  an additional 2 to 2.5 inches of rainfall that is expected by 
  Saturday afternoon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

NYZ001>006-010>013-019>021-085-170330-
/O.CON.KBUF.FF.A.0002.210717T0300Z-210718T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Northern Erie-
Genesee-Wyoming-Livingston-Chautauqua-Cattaraugus-Allegany-Southern
Erie-
Including the cities of Orchard Park, Rochester, Geneseo, Buffalo, 
Oswego, Batavia, Medina, Newark, Olean, Wellsville, Springville, 
Fair Haven, Jamestown, Niagara Falls, and Warsaw
318 PM EDT Fri Jul 16 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 11 PM EDT THIS EVENING 
THROUGH LATE SATURDAY NIGHT...

The Flash Flood Watch continues for

* Portions of central and western New York, including the following 
  counties, in central New York, Northern Cayuga and Oswego. In 
  western New York, Allegany, Cattaraugus, Chautauqua, Genesee, 
  Livingston, Monroe, Niagara, Northern Erie, Orleans, Southern 
  Erie, Wayne and Wyoming.

* From 11 PM EDT this evening through late Saturday night.

* An area of low pressure will track northeast across Ohio tonight 
  along a stationary front that stretches all the way east through 
  western and central New York. This area of low pressure will then 
  track east across western NY and the Finger Lakes region on 
  Saturday. Moderate to heavy rain will enter far western NY tonight 
  and then track eastward across the region through Saturday evening. 
  Thunderstorms are possible and due to recent substantial rainfall, 
  localized flooding is a concern. One hour flash flood guidance is 1 
  to 2 inches across a majority of the region. This could easily be 
  reached, especially if training thunderstorms or organized areas of 
  slow moving heavy rain occur near Metro areas and locations prone to 
  flooding. Rises on rivers and creeks are also expected. However, the 
  rivers and creeks of most concern at this time are the Buffalo 
  Creeks, where minor to even some moderate flooding may occur due to 
  an additional 2 to 2.5 inches of rainfall that is expected by 
  Saturday afternoon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

JM
608 
WGUS61 KBUF 170106
FFABUF

Flood Watch
National Weather Service Buffalo NY
906 PM EDT Fri Jul 16 2021

NYZ001>006-010>014-019>021-085-170915-
/O.CON.KBUF.FF.A.0002.210717T0300Z-210718T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Northern Erie-
Genesee-Wyoming-Livingston-Ontario-Chautauqua-Cattaraugus-Allegany-
Southern Erie-
Including the cities of Orchard Park, Rochester, Geneseo, Buffalo, 
Oswego, Batavia, Medina, Newark, Olean, Wellsville, Springville, 
Fair Haven, Jamestown, Canandaigua, Niagara Falls, and Warsaw
906 PM EDT Fri Jul 16 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE SATURDAY NIGHT...

The Flash Flood Watch continues for

* Portions of central and western New York, including the following 
  counties, in central New York, Northern Cayuga and Oswego. In 
  western New York, Allegany, Cattaraugus, Chautauqua, Genesee, 
  Livingston, Monroe, Niagara, Northern Erie, Ontario, Orleans, 
  Southern Erie, Wayne and Wyoming.

* Through late Saturday night.

* An area of low pressure tonight will track northeast across Ohio 
  along a stationary front that stretches all the way east through
  western and central New York. This area of low pressure will then 
  track east across western NY and the Finger Lakes region on 
  Saturday. Moderate to heavy rain will enter far western NY tonight 
  and then track eastward across the region through Saturday evening. 
  Thunderstorms are possible and due to recent substantial rainfall, 
  localized flooding is a concern. One hour flash flood guidance is 1 
  to 2 inches across a majority of the region. This could easily be 
  reached, especially if training thunderstorms or organized areas of 
  slow moving heavy rain occur near Metro areas and locations prone to 
  flooding. Rises on rivers and creeks are also expected. However, the 
  rivers and creeks of most concern at this time are the Buffalo 
  Creeks, where minor to even some moderate flooding may occur due to 
  an additional 2 to 2.5 inches of rainfall that is expected by 
  Saturday afternoon.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

DRT
003 
WGUS61 KBUF 170806
FFABUF

Flood Watch
National Weather Service Buffalo NY
406 AM EDT Sat Jul 17 2021

NYZ001>006-010>014-019>021-085-171615-
/O.CON.KBUF.FF.A.0002.000000T0000Z-210718T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Northern Erie-
Genesee-Wyoming-Livingston-Ontario-Chautauqua-Cattaraugus-Allegany-
Southern Erie-
Including the cities of Orchard Park, Rochester, Geneseo, Buffalo, 
Oswego, Batavia, Medina, Newark, Olean, Wellsville, Springville, 
Fair Haven, Jamestown, Canandaigua, Niagara Falls, and Warsaw
406 AM EDT Sat Jul 17 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* Portions of central and western New York, including the following 
  counties, in central New York, Northern Cayuga and Oswego. In 
  western New York, Allegany, Cattaraugus, Chautauqua, Genesee, 
  Livingston, Monroe, Niagara, Northern Erie, Ontario, Orleans, 
  Southern Erie, Wayne and Wyoming.

* Through late tonight.

* Steady rainfall will be heavy at times from the Niagara Frontier 
  to the Rochester area today. Storm total rainfall amounts between 
  2 and 2.5 inches will be common across this area, and this may 
  result in flash flooding. In addition, water levels will rise on 
  many Buffalo area creeks potentially resulting in flooding. 
  Elsewhere, there's a risk of thunderstorms to produce locally 
  heavy rainfall and flash flooding.

* Areas most vulnerable to flooding include urban areas, areas with 
  higher or steep terrain, and areas which received lots of rainfall 
  yesterday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Apffel
028 
WGUS61 KBUF 171555
FFABUF

Flood Watch
National Weather Service Buffalo NY
1155 AM EDT Sat Jul 17 2021

NYZ001>006-010>014-019>021-085-180000-
/O.CON.KBUF.FF.A.0002.000000T0000Z-210718T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Northern Erie-
Genesee-Wyoming-Livingston-Ontario-Chautauqua-Cattaraugus-Allegany-
Southern Erie-
Including the cities of Orchard Park, Rochester, Geneseo, Buffalo, 
Oswego, Batavia, Medina, Newark, Olean, Wellsville, Springville, 
Fair Haven, Jamestown, Canandaigua, Niagara Falls, and Warsaw
1155 AM EDT Sat Jul 17 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* Portions of central and western New York, including the following 
  counties, in central New York, Northern Cayuga and Oswego. In 
  western New York, Allegany, Cattaraugus, Chautauqua, Genesee, 
  Livingston, Monroe, Niagara, Northern Erie, Ontario, Orleans, 
  Southern Erie, Wayne and Wyoming.

* Through late tonight.

* Steady rainfall will continue to be heavy at times from the 
  Niagara Frontier to the Rochester area this afternoon. An 
  addtional 1 to 1.5 inches is expected through late today, with 
  storm total rainfall amounts between 2 and 2.5 inches will be 
  common across this area, and this may result in flash flooding. In 
  addition, water levels will continue to rise on many Buffalo area 
  creeks potentially resulting in flooding. Elsewhere, there's a 
  risk of thunderstorms to produce locally heavy rainfall and flash 
  flooding.

* Areas most vulnerable to flooding include urban areas, areas with 
  higher or steep terrain, and areas which received lots of rainfall 
  yesterday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

JM
681 
WGUS61 KBUF 172247
FFABUF

Flood Watch
National Weather Service Buffalo NY
647 PM EDT Sat Jul 17 2021

NYZ001>006-010>014-019>021-085-180600-
/O.CON.KBUF.FF.A.0002.000000T0000Z-210718T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Northern Erie-
Genesee-Wyoming-Livingston-Ontario-Chautauqua-Cattaraugus-Allegany-
Southern Erie-
Including the cities of Orchard Park, Rochester, Geneseo, Buffalo, 
Oswego, Batavia, Medina, Newark, Olean, Wellsville, Springville, 
Fair Haven, Jamestown, Canandaigua, Niagara Falls, and Warsaw
647 PM EDT Sat Jul 17 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 2 AM EDT SUNDAY...

The Flash Flood Watch continues for

* Portions of central and western New York, including the following 
  counties, in central New York, Northern Cayuga and Oswego. In 
  western New York, Allegany, Cattaraugus, Chautauqua, Genesee, 
  Livingston, Monroe, Niagara, Northern Erie, Ontario, Orleans, 
  Southern Erie, Wayne and Wyoming.

* Until 2 AM EDT Sunday.

* Steady rainfall will become focused across the Finger Lakes and 
  eastward this evening. Here an additional inch of rainfall will 
  continue the potential for flooding. Lighter rain to the west, 
  combined with continued runoff may continue to give rise to creeks 
  and streams through the evening.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

DRT
276 
WGUS61 KBUF 180227
FFABUF

Flood Watch
National Weather Service Buffalo NY
1027 PM EDT Sat Jul 17 2021

NYZ001>006-010>014-019>021-085-180330-
/O.CAN.KBUF.FF.A.0002.000000T0000Z-210718T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Northern Erie-
Genesee-Wyoming-Livingston-Ontario-Chautauqua-Cattaraugus-Allegany-
Southern Erie-
Including the cities of Orchard Park, Rochester, Geneseo, Buffalo, 
Oswego, Batavia, Medina, Newark, Olean, Wellsville, Springville, 
Fair Haven, Jamestown, Canandaigua, Niagara Falls, and Warsaw
1027 PM EDT Sat Jul 17 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of central New York and western 
New York, including the following areas, in central New York, 
Northern Cayuga and Oswego. In western New York, Allegany, 
Cattaraugus, Chautauqua, Genesee, Livingston, Monroe, Niagara, 
Northern Erie, Ontario, Orleans, Southern Erie, Wayne and Wyoming 
has been cancelled.

The Flood Watch is cancelled. Additional flooding is no longer 
expected to pose a threat. Please continue to heed remaining road 
closures.

$$

DRT

The office that day

Everything else NWS Buffalo, NY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 15, 8:06 PM EDTSpecial Weather StatementBUFErie24 min
Jul 15, 8:12 PM EDTSpecial Weather StatementBUFChautauqua63 min
Jul 15, 8:18 PM EDTSevere Thunderstorm WarningBUFChautauqua57 min
Jul 15, 9:21 PM EDTSpecial Weather StatementBUFCattaraugus54 min
Jul 15, 10:48 PM EDTSpecial Marine WarningBUF57 min
Jul 15, 11:09 PM EDTSpecial Weather StatementBUFJefferson36 min
Jul 16, 2:13 PM EDTFlash Flood WarningBUFChautauqua5 hr
Jul 16, 2:59 PM EDTFlash Flood WarningBUFCattaraugus, Chautauqua4 hr
Jul 16, 4:45 PM EDTSmall Craft AdvisoryBUF44 hr
Jul 16, 4:49 PM EDTAreal Flood WarningBUFChautauqua6 hr
Jul 16, 7:14 PM EDTAreal Flood WarningBUFChautauqua6 hr

Nearby

Flash Flood Watches in New York, 2021Every flash flood watch in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.