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This probabilistic forecast is issued by the Middle Atlantic River Forecast Center.
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About this graph
Forecasts for the Frankstown Branch Juniata River at Williamsburg are issued routinely year-round.
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Zoom Level:16
Flood Categories (in feet)
Major Flood Stage: 15
Moderate Flood Stage: 13
Flood Stage: 12
Action Stage: 9
Low Stage (in feet): 0

Historic Crests
(1) 19.46 ft on 09/18/2004
(2) 19.15 ft on 01/19/1996
(3) 19.10 ft on 06/01/1889
(4) 18.58 ft on 03/18/1936
(5) 18.39 ft on 06/23/1972
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(P): Preliminary values subject to further review.

Recent Crests
(1) 16.55 ft on 09/02/2021 (P)
(2) 16.98 ft on 09/10/2018
(3) 12.58 ft on 08/04/2018
(4) 12.63 ft on 02/17/2018
(5) 12.16 ft on 09/10/2011
Show More Recent Crests

(P): Preliminary values subject to further review.

Low Water Records
(1) 0.97 ft on 07/24/1934
(2) 1.01 ft on 08/12/1963
(3) 1.07 ft on 09/08/1969
(4) 1.10 ft on 09/10/1964
(5) 1.15 ft on 09/01/1966
Show More Low Water Records
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Gauge LocationGauge Map Marker
Latitude/Longitude Disclaimer: The gauge location shown in the above map is the approximate location based on the latitude/longitude coordinates provided to the NWS by the gauge owner.
Flood Impacts & Photos Collapse
If you notice any errors in the below information, please contact our Webmaster
26 FEMA 0.2% Annual Chance Flood Level (500-year flood).
22 FEMA 1% Annual Chance Flood Level (100-year flood).
21 FEMA 2% Annual Chance Flood Level (50-year flood). Flood waters begin to reach the Weller Road Bridge near Canoe Creek State Park.
19.5 Flood of record from the remnants of Hurricane Ivan in September 2004.
18 Most of Williamsburg is affected by high water. Very few houses on the right bank are above this level.
17.5 FEMA 10% Annual Chance Flood Level (10-year flood).
17 Many homes on the right, or south bank are affected by high water. The south approach to the highway bridge is unundated. A number of other streets and roads in the area are closed.
15 Many homes on the right, or south bank will be affected by high water.
13 Sections of route 866 from Williamsburg to Ganister are covered by flood waters.
12 The right, or south bank overflows. The Road near the river upstream of Williamsburg is inundated. A few homes experience basement flooding.
(1) looking upstream
(2) view of the gagehouse
(3) looking downstream

Other Real-time and/or Archive Data Sources:

Additional Information Collapse
Potential River Levels - Used to
Potential River Levels
Used to Estimate the Chance of Flooding and the Range of Possible River Levels
10 Day (HEFS) 7 Day (NAEFS) 7 Day (GEFS)
HEFS Ensemble NAEFS Ensemble GEFS Ensemble

Note: Use the official hydrograph at the top of this web page for river levels within the next 72 hours.

Click individual graphics to enlarge.

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The National Weather Service prepares its forecasts and other services in collaboration with agencies like the US Geological Survey, US Bureau of Reclamation, US Army Corps of Engineers, Natural Resource Conservation Service, National Park Service, ALERT Users Group, Bureau of Indian Affairs, and many state and local emergency managers across the country. For details, please click here.
NWS Information
National Weather Service
State College Weather Forecast Office
328 Innovation Boulevard, Suite 330
State College, PA 16803
(814) 231-2408
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Page last modified: 2-Nov-2020 7:30 PM
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