Tornadoes · United States · Maine · 2013

EF0 tornado, Danforth, Maine, July 17, 2013

This EF0 tornado ran 0.1 miles across Washington County on July 17, 2013, touching down at 6:48 PM EDT and reaching 50 yards wide. It killed nobody.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. EF065 to 85 mphthis tornado

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. EF186 to 110 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. EF2111 to 135 mph

    Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

  4. EF3136 to 165 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. EF4166 to 200 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. EF5over 200 mph

    Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

  7. Unrated

    The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

The record

Rating
EF0
Date
July 17, 2013
Touchdown
6:48 PM EDT (22:48 UTC)
Lifted
6:49 PM EDT (22:49 UTC)
On the ground
1 minutes
Path length
0.1 miles (0.2 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Washington County
Touchdown point
45.668, -67.877
Lift-off point
45.666, -67.876
Record number
1307171648-01

What the Weather Service recorded

A cold front and upper disturbance crossed the region during the afternoon and evening hours of the 17th. Severe thunderstorms developed across eastern Maine in advance of the front during the late afternoon hours...then persisted into the evening. The thunderstorms produced damaging winds...along with a brief tornado in the Danforth area. Heavy rain produced localized flash flooding in the Caribou area.

An EF0 tornado...embedded within an area of damaging straight-line winds...briefly touched down destroying a metal shed (DI 1, DOD5). Based on the damage...the tornado winds were estimated at 70 mph.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

Issued (UTC)ExpiredProductOffice
22:06 UTC01:00 UTCFlood AdvisoryCAR
22:30 UTC23:15 UTCSevere Thunderstorm WarningCAR
23:31 UTC04:39 UTCFlash Flood WarningCAR

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The forecast that day

The Storm Prediction Center had this point in a Slight Risk. The outlook in force was issued at 19:47 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The air that afternoon

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

Caribou, ME (KCAR), 12:00Z

10.8 hours before the tornado, 134 km from the path. July 17, 2013.

Skew-T log-pSkew-T log-p diagram, Caribou, ME at 12:00Z on 2013-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -83244, lifted condensation level 1314 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Caribou, ME at 12:00Z on 2013-07-17The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 143 square meters per square second, 0 to 6 km bulk shear 39 knots.193958Sfc1 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. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
-83244 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1314 m above ground
0-6 km bulk shear
39 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
143 m²/s²
0-3 km storm-relative helicity
168 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.5 K/km

Open this sounding in Storm Lab

Caribou, ME (KCAR), 00:00Z

1.2 hours after it, 134 km from the path. July 18, 2013.

Skew-T log-pSkew-T log-p diagram, Caribou, ME at 00:00Z on 2013-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 275 joules per kilogram, CIN -76, lifted condensation level 696 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Caribou, ME at 00:00Z on 2013-07-18The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 45 square meters per square second, 0 to 6 km bulk shear 20 knots.193958Sfc1 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. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
275 J/kg
Mixed-layer CIN
-76 J/kg
Surface CAPE
115 J/kg
Mixed-layer LCL
696 m above ground
0-6 km bulk shear
20 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
45 m²/s²
0-3 km storm-relative helicity
70 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.7 K/km

Open this sounding in Storm Lab

The surface observations

Houlton International Airport (HUL), 51 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
20:53 UTC7868 5 kt1012.9
21:43 UTC73.468210° 5 kt1012.9VCTS -RA
21:53 UTC7269220° 6 kt1013.2VCTS -RA BR
22:15 UTC71.668190° 10 kt201012.9TSRA BR
22:23 UTC69.868180° 7 kt151012.2-TSRA BR
22:46 UTC69.868240° 9 kt1012.9VCTS RA BR
22:53 UTC6967210° 11 kt1012.5VCTS +RA BR
23:05 UTC69.866.2170° 8 kt221013.2+TSRA FG
23:36 UTC6864.4190° 9 kt171012.9VCTS -RA BR
23:38 UTC6864.4190° 10 kt171012.9VCTS -RA BR
23:47 UTC69.866.2160° 14 kt191012.2VCTS +RA BR
23:51 UTC69.866.2160° 13 kt191012.2RA BR
23:53 UTC6966180° 10 kt191012.5RA BR
23:56 UTC69.866.2160° 9 kt191012.5-RA BR
00:13 UTC69.864.4 4 kt151013.5-TSRA
00:46 UTC6866.290° 6 kt1015.6VCTS +RA BR

From the Iowa Environmental Mesonet's archive of airport observations.

The radar

The Caribou radar (KCBW), 42 km away, was scanning. The volume nearest the touchdown began at 22:46 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
22:45 UTCTSTM WND DMG2 Nnw DanforthAroostook, MENUMEROUS TREES DOWN ALONG BANCROFT RD IN WESTON
22:51 UTCTSTM WND DMGSsw DanforthWashington, MEWIRES DOWN ALONG RT 169 IN DANFORTH. TIME ESTIMATED.
23:00 UTCTSTM WND DMG3 Nw DanforthAroostook, MENUMEROUS TREES AND POWER LINES DOWN
01:00 UTCFLASH FLOODOrientAroostook, METIME ESTIMATED
01:30 UTCFLASH FLOOD6 Nw DanforthAroostook, MEDELAYED REPORT. KELLY RD NEAR SHOREY BROOK WASHED OUT.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2013 tornado in MaineEvery tornado in Maine since 1950Warnings in force in Maine nowThe forecast where you are

What this means

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

Sources

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.