####018004619#### FGUS71 KPHI 141445 ESFPHI DEC001-003-005-MDC011-015-029-035-041-NJC001-005-007-009-011-015- 019-021-023-025-027-029-033-035-037-041-PAC011-017-025-029-045- 077-089-091-095-101-150245- Winter/Spring Flood Potential Outlook National Weather Service Mount Holly NJ 1045 AM EDT Thu Mar 14 2024 Winter/Spring Flood Potential Outlook...Number 6 This is the sixth in a series of annual Flood Potential Statements that provides an assessment of how ready or primed our forecast area is for river flooding. This outlook covers the middle/lower Delaware, Lehigh, Schuylkill, Passaic and Raritan River basins. It will provide information on flood threat contributors such as recent precipitation, soil moisture, snow cover and its water equivalent, river ice conditions, streamflow, future precipitation and others. This assessment is valid between March 14 - 28, 2024. In the Mid-Atlantic region, heavy rainfall is the primary factor which leads to river flooding. It is important to note that heavy rainfall can rapidly cause river flooding any time of year, even when the overall river flood potential is considered to be low. This outlook does not discuss flash flooding, nor does it discuss any extent or severity of flooding. In the Mount Holly, New Jersey Hydrologic Service Area (HSA), the overall river flood potential is above normal. Note - For the headwaters of the Delaware River, see the statement (FGUS71 KBGM ESFBGM) from our Binghamton (BGM) New York office. CURRENT FLOODING - None. There is currently no river flooding occurring within our service area. RECENT PRECIPITATION - Much above normal. Between 5.0 and 6.5 inches of liquid have been recorded over the last 30 days across the entire HSA. Precipitation departure maps can be found at www.weather.gov/marfc (under the Water Supply tab). SNOW COVER - There is no snow on the ground across our forecast area. Depth and basin-average water equivalent estimates can be found at www.weather.gov/marfc (under the Seasonal Interest tab) or www.nohrsc.noaa.gov (under the National Analysis tab). RIVER ICE - We have no reports of river ice across our area of responsibility at this time. STREAMFLOW - Normal to much above normal. Real time water data is available from the United States Geological Survey (USGS) by visiting https://dashboard.waterdata.usgs.gov. SOIL MOISTURE - Normal to above normal. Soil moisture monitoring charts (Long Term Palmer Drought Severity Index) from NOAA's Climate Prediction Center can be found at the following websites... www.cpc.ncep.noaa.gov/products/analysis_monitoring/regional_ monitoring/palmer.gif as well as www.drought.gov. GROUND WATER - USGS monitoring wells indicate that current ground water levels across the region vary and are running below normal to above normal. Additonal information can be found at https://dashboard.waterdata.usgs.gov. RESERVOIR CONDITIONS - Water supply and flood control reservoirs in the area are mainly running normal. FUTURE WEATHER CONDITIONS - High pressure to our south will drift off the Southeast coast through today. Low pressure will pass north of our area tonight through Friday. A pair of cold fronts will pass through Sunday and Monday before high pressure returns for the middle of next week. At this time and in general, it appears the region will see about 0.25 to 0.50 inch of rainfall over the next week. While this is not enough rain to drive river flooding, keep in mind the region remains primed for flooding with high levels of ground moisture and high streamflows in place. Under the current environment, a precipitation event that results in 1.50 to 2.00 inches of rainfall would likely cause river flooding. For week two, the 8 to 14 day outlook calls for above normal temperatures and precipitation. SUMMARY - Taking all of the included variables into consideration, the overall river flood potential is above normal across the forecast area. For complete weather information, visit our website at: www.weather.gov/phi && Overall Flood Potential...Above normal Current Flooding...None Recent Precipitation...Much above normal Snow cover...Below normal north, normal south River Ice...Below normal north, normal south Streamflow...Much above normal Soil Moisture...Normal to above normal Ground Water...Below normal to above normal Reservoir Conditions...Normal $$ Kruzdlo ####018009389#### FGUS73 KMQT 141447 ESFMQT MIC013-053-061-071-103-131-141600- Probabilistic Hydrologic Outlook National Weather Service Marquette MI 944 AM EDT Thu Mar 14 2024 ...2024 SPRING FLOOD AND WATER RESOURCES OUTLOOK... This Spring Flood and Water Resources Outlook is for the rivers in western and east-central Upper Michigan. ...Flood Outlook Highlights... The overall flood risk this spring is much below-normal across all of Upper Michigan. The primary factors contributing to a below- normal flood risk are significantly below normal snowpack and a lack of river ice. ...Flood Terminology... The term minor flooding is used to indicate minimal or no property damage. However, some public inconvenience is possible. The term moderate flooding is used to indicate some inundations of structures and roads near streams. Some evacuations of people and/or transfer of property to higher elevations may be needed. The term major flooding is used to indicate extensive inundation of structure and roads. Significant evacuations of people and/or transfer of property to higher elevations will be needed. ...Probabilistic Outlook... The chance of minor flooding is less than 20% at all of the Upper Michigan forecast locations except Witch Lake (30%) along the Michigamme River and Alston (34%) along the Sturgeon River. The chance of moderate flooding is 5% or less at all of the Upper Michigan forecast locations except Witch Lake (17%) along the Sturgeon River. ...Past Precipitation... Precipitation last Fall was below normal across the area and this dry pattern has continued through the end of February. ...River Conditions... Streamflow across Upper Michigan was near to below-normal and persistently warm temperatures combined with episodes of snowmelt has removed most of the river ice. ...Soil Moisture and Frost Depths... Soil moisture is below-normal across Upper Michigan due to persistently warm and dry conditions since last fall. Frost depth in Negaunee Township was 3 inches on Feb 27th and hasn't changed much since mid-January when the seasonal snowpack was established. ...Snow Cover and Liquid Water Content... Current snow water equivalent values are 0-25% of normal across all of Upper Michigan except the Michigamme Highlands and the northern Keweenaw Peninsula where SWE values were 25-50% of normal. Even though the U.P. winter is far from over, snowpack is at near- to record-low values and there aren't any major storm systems in the forecast at this time. ...River Ice Conditions... Much above-normal temperatures this winter limited ice formation and episodes of snowmelt cleared out what formed on rivers across Upper Michigan. Despite the recent cold snap, above-normal temperatures are forecast to continue into spring suggesting much below-normal potential for ice jams and associated flooding. ...Weather Outlook... The single biggest factor affecting spring flood risks are the weather conditions during the period of snow melt. A slow snow melt with little or no rainfall would elinimate this years flood risks. On the other hand, a rapid warmup accompanied by heavy rain substantially increases flood risks for portions of Upper Michigan with a few inches of lingering snow water equivalent. At this time, the Climate Prediction Center's probabilistic forecast is for 33-50% chance of below normal precipitation and above-normal temperatures continuing through March. The current threat for springtime flooding is much below-normal, but much of the Spring Flooding Outlook hinges on weather conditions over the next 4 to 8 weeks. ...Definitions... In Table 1 below...the current (CS) and historical (HS) or normal probabilities of exceeding minor...moderate...and major flood stages are listed for the valid time period. CS values indicate the probability of reaching a flood category based on current conditions. HS values indicate the probability of reaching a flood category based on historical or normal conditions. When the value of CS is more than HS, the probability of exceeding that level is higher than normal. When the value of CS is less than HS...the probability of exceeding that level is lower than normal. ...Table 1--Probabilities for minor...moderate and major flooding... Valid Period: 03/18/2024 - 06/16/2024 : Current and Historical : Chances of Exceeding : Flood Categories : as a Percentage (%) Categorical : Flood Stages (FT) : Minor Moderate Major Location Minor Mod Major : CS HS CS HS CS HS -------- ----- ----- ----- : --- --- --- --- --- --- :Michigamme River Witch Lake 9.0 10.0 12.0 : <5 30 <5 17 <5 6 :Paint River Crystal Falls (Pa 7.0 8.0 9.5 : <5 18 <5 5 <5 <5 :Black River Bessemer 10.0 12.0 14.0 : <5 13 <5 <5 <5 <5 :Ontonagon River Rockland 25.0 26.0 28.0 : <5 <5 <5 <5 <5 <5 :Sturgeon River Sidnaw 12.0 15.0 17.0 : <5 <5 <5 <5 <5 <5 Alston 8.0 11.0 14.0 : <5 34 <5 <5 <5 <5 :Chocolay River Harvey 10.0 11.5 13.0 : <5 <5 <5 <5 <5 <5 :East Branch Escanaba River Gwinn 7.0 9.0 12.0 : <5 6 <5 <5 <5 <5 :Middle Branch Escanaba River Humboldt 6.5 8.0 9.0 : <5 13 <5 <5 <5 <5 Legend CS = Conditional Simulation (Current Outlook) HS = Historical Simulation FT = Feet In Table 2 below, the 95 through 5 percent columns indicate the probability of exceeding the listed stage levels (FT) for the valid time period. ...Table 2--Exceedance Probabilities... Chance of Exceeding Stages at Specific Locations Valid Period: 03/18/2024 - 06/16/2024 Location 95% 90% 75% 50% 25% 10% 5% -------- ------ ------ ------ ------ ------ ------ ------ :Michigamme River Witch Lake 4.0 4.2 4.7 5.1 5.9 6.4 7.2 :Paint River Crystal Falls (Pa 3.2 3.3 3.6 4.0 4.6 5.2 5.5 :Black River Bessemer 3.1 3.4 3.9 4.7 6.0 7.4 9.2 :Ontonagon River Rockland 7.4 8.3 8.8 10.4 12.4 14.5 15.7 :Sturgeon River Sidnaw 5.0 5.2 5.6 6.0 6.4 6.9 7.2 Alston 4.9 5.0 5.5 6.0 6.6 7.3 7.6 :Chocolay River Harvey 3.2 3.3 3.7 4.2 4.8 6.0 7.2 :East Branch Escanaba River Gwinn 2.1 2.2 2.8 3.3 3.8 4.5 4.9 :Middle Branch Escanaba River Humboldt 3.1 3.2 3.8 4.4 4.8 5.3 5.3 In Table 3 below, the 95 through 5 percent columns indicate the probability of falling below the listed stage levels (FT) for the valid time period. ...Table 3--Nonexceedance Probabilities... Chance of Falling Below Stages at Specific Locations Valid Period: 03/18/2024 - 06/16/2024 Location 95% 90% 75% 50% 25% 10% 5% -------- ------ ------ ------ ------ ------ ------ ------ :Michigamme River Witch Lake 3.3 3.3 3.2 3.0 2.9 2.8 2.8 :Paint River Crystal Falls (Pa 2.4 2.3 2.3 2.3 2.2 2.1 2.1 :Black River Bessemer 2.4 2.4 2.4 2.3 2.1 2.0 1.9 :Ontonagon River Rockland 5.9 5.9 5.7 5.6 5.5 5.4 5.3 :Sturgeon River Sidnaw 4.4 4.3 4.3 4.1 4.0 3.9 3.9 Alston 4.3 4.2 4.2 4.0 3.9 3.8 3.7 :Chocolay River Harvey 2.8 2.8 2.8 2.8 2.8 2.7 2.7 :East Branch Escanaba River Gwinn 0.9 0.9 0.8 0.8 0.7 0.5 0.4 :Middle Branch Escanaba River Humboldt 2.1 2.1 2.1 2.0 2.0 1.9 1.8 These long-range probabilistic outlooks contain forecast values that are calculated using multiple season scenarios from 30 or more years of climatological data, including current conditions of the river, soil moisture, snow cover, and 30 to 90 day long-range outlooks of temperature and precipitation. By providing a range of probabilities, the level of risk associated with long-range planning decisions can be determined. These probabilistic forecasts are part of the National Weather Service's Advanced Hydrologic Prediction Service. Visit our web site weather.gov/mqt for more weather and water information. This is the final spring flood and water resources outlook planned for the spring 2024 season. $$