Alert archive / New Jersey / Mercer County

Weather alerts in Mercer County, New Jersey, 2010

210 weather alerts in 2010, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Mercer County and its neighbors

Each county as a circle sized by its count in 2010. Tap one for its archive.

Alerts: 210
Warnings: 57
Watches: 39
Advisories: 32
Busiest month: July41 alerts
Busiest day: October 1, 201012 alerts

Over time

By month

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

Mercer County, 2010

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	0			0
Severe thunderstorm warnings	16	12	25%	8	38%	24 min
Flash flood warnings	2	0	100%	0

Each office's whole area, 2010

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Philadelphia/Mount Holly: tornado warnings	12	1	92%	4	25%	1 min
NWS Philadelphia/Mount Holly: severe thunderstorm warnings	183	107	42%	252	82%	29 min
NWS Philadelphia/Mount Holly: flash flood warnings	14	2	86%	15	60%	45 min

An office's figures cover every county it serves, including across state lines.

Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.

The alerts

Every alert, in the order issued. Times are local, Eastern Time. Each opens its own page with the text, the map, the radar and the sounding.

Issued	Product	Office	Lasted
Dec 31, 8:48 PM EST	Winter Weather Advisory	PHI	4 hr
Jan 2, 10:45 AM EST	Wind Advisory	PHI	32 hr
Jan 23, 3:38 PM EST	Flood Watch	PHI	49 hr
Jan 24, 3:13 PM EST	Wind Advisory	PHI	22 hr
Jan 25, 10:15 AM EST	Areal Flood Advisory	PHI	6 hr
Jan 25, 11:19 AM EST	Areal Flood Advisory	PHI	29 days
Feb 4, 3:23 AM EST	Winter Storm Watch	PHI	10 hr
Feb 4, 1:43 PM EST	Winter Storm Warning	PHI	51 hr
Feb 8, 3:45 AM EST	Winter Storm Watch	PHI	24 hr
Feb 8, 3:51 PM EST	Winter Storm Warning	PHI	54 hr
Feb 10, 4:33 AM EST	Blizzard Warning	PHI	19 hr
Feb 10, 7:27 AM EST	Mesoscale Discussion	SPC	5 hr
Feb 10, 12:20 PM EST	Mesoscale Discussion	SPC	4 hr
Feb 15, 3:40 AM EST	Winter Weather Advisory	PHI	36 hr
Feb 23, 3:30 PM EST	Winter Storm Watch	PHI	24 hr
Feb 24, 3:16 PM EST	Winter Storm Warning	PHI	48 hr
Feb 25, 11:17 AM EST	Wind Advisory	PHI	24 hr
Feb 26, 12:44 AM EST	Mesoscale Discussion	SPC	4 hr
Mar 11, 3:42 PM EST	Flood Watch	PHI	59 hr
Mar 12, 2:35 AM EST	Wind Advisory	PHI	46 hr
Mar 13, 10:48 AM EST	Areal Flood Advisory	PHI	7 hr
Mar 13, 2:01 PM EST	High Wind Warning	PHI	8 hr
Mar 13, 4:20 PM EST	River Flood Warning	PHI	14 hr
Mar 13, 6:04 PM EST	Areal Flood Warning	PHI	8 hr
Mar 14, 1:47 AM EST	Areal Flood Warning	PHI	20 hr
Mar 21, 3:26 PM EDT	Flood Watch	PHI	37 hr
Mar 22, 8:25 PM EDT	Areal Flood Warning	PHI	15 hr
Mar 27, 3:39 PM EDT	Flood Watch	PHI	3 days
Mar 30, 1:35 PM EDT	Areal Flood Warning	PHI	8 hr
Mar 30, 3:18 PM EDT	River Flood Warning	PHI	8 hr
Mar 30, 9:28 PM EDT	Areal Flood Warning	PHI	16 hr
Apr 5, 10:00 AM EDT	Fire Weather Watch	PHI	18 hr
Apr 5, 10:00 AM EDT	Red Flag Warning	PHI	8 hr
Apr 6, 3:30 PM EDT	Fire Weather Watch	PHI	13 hr
Apr 7, 4:02 AM EDT	Red Flag Warning	PHI	17 hr
Apr 10, 10:50 AM EDT	Red Flag Warning	PHI	8 hr
Apr 27, 2:34 PM EDT	Fire Weather Watch	PHI	14 hr
Apr 28, 4:12 AM EDT	Fire Weather Watch	PHI	16 hr
Apr 28, 4:12 AM EDT	Red Flag Warning	PHI	16 hr
Apr 28, 7:55 PM EDT	Red Flag Warning	PHI	24 hr
May 3, 12:16 AM EDT	Severe Thunderstorm Warning	PHI	34 min
May 3, 12:30 AM EDT	Areal Flood Advisory	PHI	3 hr
May 3, 1:51 AM EDT	Areal Flood Advisory	PHI	6 hr
May 3, 7:21 AM EDT	Areal Flood Advisory	PHI	3 hr
May 4, 4:04 PM EDT	Severe Thunderstorm Warning	PHI	56 min
May 8, 4:15 AM EDT	Wind Advisory	PHI	25 hr
May 8, 2:02 PM EDT	Red Flag Warning	PHI	6 hr
May 8, 7:59 PM EDT	Fire Weather Watch	PHI	8 hr
May 9, 4:02 AM EDT	Red Flag Warning	PHI	16 hr
May 9, 3:57 PM EDT	Fire Weather Watch	PHI	12 hr
May 10, 4:17 AM EDT	Red Flag Warning	PHI	16 hr
May 10, 2:32 PM EDT	Frost Advisory	PHI	17 hr
May 14, 3:43 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
May 14, 6:25 PM EDT	Severe Thunderstorm Warning	PHI	65 min
May 14, 6:35 PM EDT	Mesoscale Discussion	SPC	55 min
May 14, 6:58 PM EDT	Special Weather Statement	PHI	62 min
May 14, 7:04 PM EDT	Severe Thunderstorm Warning	PHI	56 min
May 27, 1:23 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
May 27, 7:40 PM EDT	Special Weather Statement	PHI	65 min
May 29, 10:03 PM EDT	Special Weather Statement	PHI	57 min
May 31, 4:37 PM EDT	Special Weather Statement	PHI	38 min
May 31, 4:56 PM EDT	Special Weather Statement	PHI	49 min
May 31, 5:03 PM EDT	Special Weather Statement	PHI	57 min
May 31, 5:18 PM EDT	Special Weather Statement	PHI	42 min
May 31, 5:40 PM EDT	Areal Flood Advisory	PHI	110 min
May 31, 6:49 PM EDT	River Flood Warning	PHI	86 min
Jun 1, 2:23 PM EDT	Special Weather Statement	PHI	67 min
Jun 3, 1:32 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 3, 3:36 PM EDT	Mesoscale Discussion	SPC	54 min
Jun 4, 2:39 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Jun 4, 4:24 PM EDT	Mesoscale Discussion	SPC	66 min
Jun 4, 7:03 PM EDT	Mesoscale Discussion	SPC	57 min
Jun 6, 10:25 AM EDT	Mesoscale Discussion	SPC	65 min
Jun 6, 11:08 AM EDT	Tornado Watch	SPC	8 hr
Jun 6, 2:38 PM EDT	Mesoscale Discussion	SPC	67 min
Jun 13, 12:58 PM EDT	Mesoscale Discussion	SPC	2 hr
Jun 21, 3:00 PM EDT	Excessive Heat Watch	PHI	37 hr
Jun 22, 4:38 AM EDT	Excessive Heat Warning	PHI	60 hr
Jun 22, 5:06 PM EDT	Severe Thunderstorm Watch	SPC	4 hr
Jun 22, 6:50 PM EDT	Special Weather Statement	PHI	55 min
Jun 22, 6:59 PM EDT	Mesoscale Discussion	SPC	61 min
Jun 24, 12:16 PM EDT	Mesoscale Discussion	SPC	89 min
Jun 24, 12:28 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Jun 24, 3:07 PM EDT	Mesoscale Discussion	SPC	53 min
Jun 25, 1:38 PM EDT	Excessive Heat Watch	PHI	26 hr
Jun 26, 3:36 PM EDT	Excessive Heat Warning	PHI	51 hr
Jun 28, 12:49 PM EDT	Mesoscale Discussion	SPC	56 min
Jun 28, 1:12 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 28, 3:53 PM EDT	Mesoscale Discussion	SPC	2 hr
Jun 28, 4:29 PM EDT	Special Weather Statement	PHI	61 min
Jun 29, 9:22 AM EDT	Red Flag Warning	PHI	11 hr
Jun 30, 4:12 AM EDT	Red Flag Warning	PHI	16 hr
Jul 1, 3:55 AM EDT	Red Flag Warning	PHI	16 hr
Jul 4, 3:21 PM EDT	Excessive Heat Watch	PHI	12 hr
Jul 5, 3:00 AM EDT	Excessive Heat Warning	PHI	65 hr
Jul 7, 3:33 AM EDT	Excessive Heat Watch	PHI	24 hr
Jul 7, 12:55 PM EDT	Red Flag Warning	PHI	9 hr
Jul 8, 3:26 AM EDT	Excessive Heat Warning	PHI	12 hr
Jul 10, 9:30 AM EDT	Areal Flood Advisory	PHI	4 hr
Jul 12, 11:21 PM EDT	Special Weather Statement	PHI	84 min
Jul 13, 9:17 AM EDT	Areal Flood Advisory	PHI	118 min
Jul 13, 10:28 AM EDT	Flash Flood Warning	PHI	3 hr
Jul 13, 10:38 AM EDT	Areal Flood Advisory	PHI	3 hr
Jul 13, 10:39 AM EDT	Mesoscale Discussion	SPC	66 min
Jul 13, 2:48 PM EDT	Flash Flood Watch	PHI	19 hr
Jul 13, 3:00 PM EDT	Special Weather Statement	PHI	60 min
Jul 13, 3:08 PM EDT	Excessive Heat Watch	PHI	63 hr
Jul 13, 8:19 PM EDT	Special Weather Statement	PHI	71 min
Jul 14, 3:59 AM EDT	Areal Flood Advisory	PHI	3 hr
Jul 14, 10:15 AM EDT	Flash Flood Watch	PHI	9 hr
Jul 14, 2:36 PM EDT	Areal Flood Advisory	PHI	3 hr
Jul 14, 3:12 PM EDT	Flash Flood Warning	PHI	63 min
Jul 14, 7:58 PM EDT	Special Weather Statement	PHI	62 min
Jul 16, 4:00 AM EDT	Excessive Heat Watch	PHI	36 hr
Jul 16, 4:00 AM EDT	Heat Advisory	PHI	16 hr
Jul 16, 4:07 PM EDT	Heat Advisory	PHI	23 hr
Jul 19, 1:17 PM EDT	Mesoscale Discussion	SPC	58 min
Jul 19, 7:39 PM EDT	Mesoscale Discussion	SPC	96 min
Jul 21, 12:38 PM EDT	Mesoscale Discussion	SPC	67 min
Jul 21, 1:32 PM EDT	Severe Thunderstorm Watch	SPC	9 hr
Jul 21, 3:41 PM EDT	Mesoscale Discussion	SPC	64 min
Jul 21, 7:00 PM EDT	Mesoscale Discussion	SPC	90 min
Jul 21, 10:41 PM EDT	Special Weather Statement	PHI	94 min
Jul 22, 2:06 PM EDT	Excessive Heat Watch	PHI	25 hr
Jul 23, 3:24 PM EDT	Excessive Heat Warning	PHI	48 hr
Jul 24, 8:23 PM EDT	Mesoscale Discussion	SPC	67 min
Jul 25, 10:48 AM EDT	Mesoscale Discussion	SPC	27 min
Jul 25, 11:29 AM EDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 25, 12:50 PM EDT	Mesoscale Discussion	SPC	55 min
Jul 25, 2:41 PM EDT	Severe Thunderstorm Warning	PHI	64 min
Jul 25, 3:10 PM EDT	Severe Thunderstorm Warning	PHI	80 min
Jul 25, 3:25 PM EDT	Mesoscale Discussion	SPC	65 min
Jul 29, 1:56 PM EDT	Special Weather Statement	PHI	94 min
Aug 4, 2:56 PM EDT	Heat Advisory	PHI	29 hr
Aug 9, 2:45 PM EDT	Heat Advisory	PHI	29 hr
Aug 16, 12:05 PM EDT	Severe Thunderstorm Watch	SPC	9 hr
Aug 16, 2:17 PM EDT	Mesoscale Discussion	SPC	88 min
Aug 16, 4:27 PM EDT	Special Weather Statement	PHI	63 min
Aug 16, 4:31 PM EDT	Severe Thunderstorm Warning	PHI	59 min
Aug 16, 7:16 PM EDT	Mesoscale Discussion	SPC	59 min
Aug 22, 3:19 PM EDT	Mesoscale Discussion	SPC	56 min
Sep 4, 4:19 AM EDT	Red Flag Warning	PHI	13 hr
Sep 7, 4:27 AM EDT	Fire Weather Watch	PHI	11 hr
Sep 7, 3:42 PM EDT	Red Flag Warning	PHI	27 hr
Sep 13, 6:06 PM EDT	Mesoscale Discussion	SPC	54 min
Sep 13, 7:00 PM EDT	Special Weather Statement	PHI	60 min
Sep 13, 7:40 PM EDT	Severe Thunderstorm Warning	PHI	22 min
Sep 14, 11:00 AM EDT	Red Flag Warning	PHI	7 hr
Sep 16, 4:37 PM EDT	Mesoscale Discussion	SPC	53 min
Sep 16, 4:47 PM EDT	Special Weather Statement	PHI	43 min
Sep 16, 4:55 PM EDT	Severe Thunderstorm Warning	PHI	80 min
Sep 22, 3:10 PM EDT	Mesoscale Discussion	SPC	65 min
Sep 22, 3:43 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Sep 22, 7:14 PM EDT	Mesoscale Discussion	SPC	61 min
Sep 22, 7:54 PM EDT	Severe Thunderstorm Warning	PHI	36 min
Sep 22, 8:05 PM EDT	Special Weather Statement	PHI	55 min
Sep 22, 8:17 PM EDT	Severe Thunderstorm Warning	PHI	28 min
Sep 28, 12:45 AM EDT	Special Weather Statement	PHI	30 min
Sep 28, 8:00 AM EDT	Mesoscale Discussion	SPC	2 hr
Sep 28, 10:58 AM EDT	Tornado Watch	SPC	7 hr
Sep 28, 1:50 PM EDT	Mesoscale Discussion	SPC	55 min
Sep 29, 3:52 AM EDT	Flood Watch	PHI	49 hr
Sep 29, 3:24 PM EDT	Wind Advisory	PHI	38 hr
Sep 30, 10:49 AM EDT	Mesoscale Discussion	SPC	116 min
Sep 30, 8:29 PM EDT	Mesoscale Discussion	SPC	91 min
Sep 30, 8:35 PM EDT	Special Weather Statement	PHI	85 min
Sep 30, 9:50 PM EDT	Special Weather Statement	PHI	85 min
Oct 1, 12:01 AM EDT	Mesoscale Discussion	SPC	89 min
Oct 1, 2:04 AM EDT	Mesoscale Discussion	SPC	26 min
Oct 1, 3:02 AM EDT	Special Weather Statement	PHI	58 min
Oct 1, 3:11 AM EDT	Areal Flood Warning	PHI	12 hr
Oct 1, 3:29 AM EDT	Severe Thunderstorm Warning	PHI	61 min
Oct 1, 4:28 AM EDT	Areal Flood Warning	PHI	10 hr
Oct 1, 10:54 AM EDT	River Flood Warning	PHI	18 hr
Oct 1, 10:54 AM EDT	River Flood Warning	PHI	10 hr
Oct 1, 10:54 AM EDT	River Flood Warning	PHI	10 hr
Oct 11, 3:19 PM EDT	Mesoscale Discussion	SPC	56 min
Oct 11, 3:38 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Oct 11, 6:07 PM EDT	Mesoscale Discussion	SPC	83 min
Oct 11, 9:51 PM EDT	Special Weather Statement	PHI	114 min
Oct 11, 10:34 PM EDT	Special Weather Statement	PHI	56 min
Oct 11, 11:29 PM EDT	Special Weather Statement	PHI	61 min
Oct 12, 1:21 AM EDT	Special Weather Statement	PHI	54 min
Oct 27, 11:54 AM EDT	Mesoscale Discussion	SPC	66 min
Nov 8, 3:19 AM EST	Wind Advisory	PHI	11 hr
Nov 14, 11:02 PM EST	Dense Fog Advisory	PHI	11 hr
Nov 16, 3:27 PM EST	Wind Advisory	PHI	27 hr
Nov 17, 3:13 AM EST	Severe Thunderstorm Warning	PHI	62 min
Nov 17, 3:28 AM EST	Severe Thunderstorm Warning	PHI	62 min
Nov 30, 3:15 PM EST	Wind Advisory	PHI	23 hr
Dec 1, 2:40 AM EST	Special Weather Statement	PHI	65 min
Dec 1, 4:02 AM EST	Special Weather Statement	PHI	58 min
Dec 1, 5:07 AM EST	Special Weather Statement	PHI	53 min
Dec 1, 7:43 AM EST	Special Weather Statement	PHI	47 min
Dec 1, 8:36 AM EST	Special Weather Statement	PHI	54 min
Dec 1, 8:58 AM EST	Areal Flood Advisory	PHI	6 hr
Dec 1, 9:31 AM EST	Special Weather Statement	PHI	59 min
Dec 1, 10:49 AM EST	Special Weather Statement	PHI	56 min
Dec 1, 11:48 AM EST	Special Weather Statement	PHI	57 min
Dec 1, 12:12 PM EST	Severe Thunderstorm Warning	PHI	63 min
Dec 1, 12:59 PM EST	Areal Flood Advisory	PHI	4 hr
Dec 1, 1:16 PM EST	Severe Thunderstorm Warning	PHI	44 min
Dec 15, 8:11 AM EST	Special Weather Statement	PHI	49 min
Dec 25, 4:16 AM EST	Winter Storm Watch	PHI	11 hr
Dec 25, 3:24 PM EST	Winter Storm Warning	PHI	38 hr
Dec 26, 6:56 AM EST	Mesoscale Discussion	SPC	6 hr
Dec 26, 12:31 PM EST	Mesoscale Discussion	SPC	6 hr
Dec 26, 6:26 PM EST	Mesoscale Discussion	SPC	6 hr
Dec 27, 2:49 AM EST	Mesoscale Discussion	SPC	4 hr
Dec 27, 4:14 AM EST	Wind Advisory	PHI	17 hr

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

Product	Alerts
Severe storms
Severe Thunderstorm Warning	16
Severe Thunderstorm Watch	12
Tornado Watch	2
Mesoscale Discussion	45
Special Weather Statement	37
Flooding
Areal Flood Warning	7
Flash Flood Warning	2
River Flood Warning	6
Flash Flood Watch	2
Flood Watch	5
Areal Flood Advisory	14
Winter
Blizzard Warning	1
Winter Storm Warning	4
Winter Storm Watch	4
Winter Weather Advisory	2
Heat
Excessive Heat Warning	5
Excessive Heat Watch	7
Heat Advisory	4
Cold
Frost Advisory	1
Wind and dust
High Wind Warning	1
Wind Advisory	10
Fire
Red Flag Warning	15
Fire Weather Watch	7
Fog and smoke
Dense Fog Advisory	1

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2009 2011

Sources

National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Warning verification from the Mesonet's Cow. Rebuilt daily.