jeff dobur senior hydrologist southeast river forecast center noaa - national weather service
DESCRIPTION
Jeff Dobur Senior Hydrologist Southeast River Forecast Center NOAA - National Weather Service. Water Supply. Implications of the Seasonal Outlook for ACF. Big Picture – Past to Current Conditions Early Winter – Ensemble Streamflow Forecasts La Niña and Past S treamflows - PowerPoint PPT PresentationTRANSCRIPT
Jeff DoburSenior Hydrologist
Southeast River Forecast CenterNOAA - National Weather Service
Water SupplyImplications of the Seasonal Outlook for ACF
1. Big Picture – Past to Current Conditions2. Early Winter – Ensemble Streamflow Forecasts3. La Niña and Past Streamflows4. La Niña and Lake Lanier
Big Picture – Past to Current ConditionsTrends in Winter Rainfall for Georgia
Rainfall Accumulations Dec-Feb
Big Picture – Past to Current ConditionsTrends in Spring Rainfall for Georgia
Rainfall Accumulations Feb-Apr
Big Picture – Past to Current ConditionsTrends in Summer Rainfall for Georgia
Rainfall Accumulations May-Jul
Big Picture – Past to Current ConditionsTrends in Summer Temperature for Georgia
Average Temperature Jun-Aug
Big Picture – Past to Current ConditionsTrends in Tropical Rainfall for Georgia
Rainfall Accumulations Aug-Oct
Alberto
Frances, etc
Sept ATL Floods
Big Picture – Past to Current ConditionsTrends in Autumn Rainfall for Georgia
Rainfall Accumulations Sep-Nov
Big Picture – Past to Current ConditionsTrends in Recharge Rainfall for Lake Lanier
Rainfall Accumulations Dec-Mar for Climate Division 2 and 3
Climate Division 2 Climate Division 3
La Niña and Past Georgia Streamflows
Period Type Percent of Georgia Streamflows to Normal for the Period*
1954-1956 Mod to Strong 50 -70
1964-1965 Mod 120-180
1970-1972 Mod 80-110
1973-1976 Mod to Strong 100-150
1988-1989 Mod to Strong 50-80
1998-2000 Mod to Strong 50-80
2007-2008 Mod 50-60
2010-2011 Mod? ???
* Note: Streamflow % based on USGS Historical Runoff Values that are derived from streamflows
ApalachicolaWatershed
La Niña and Past Apalachicola Streamflows
Period Type Percent of Apalachicola HUC0313 Streamflows to Normal for the Period*
1954-1956 Mod to strong 50 -60
1964-1965 Mod 130-160
1970-1972 Mod 90-120
1973-1976 Mod to Strong 110-160
1988-1989 Mod to Strong 70-80
1998-2000 Mod to Strong 40-80
2007-2008 Mod 40-60
2010-2011 Mod? ???
* Note: Streamflow % based on USGS Historical Runoff Values that are derived from streamflows
La Niña and Past Apalachicola Streamflows
Period Type Autumn Winter Spring Summer
1954-1956 Mod/Strong 50 -60 60-70 60-70 50-80
1964-1965 Mod 130-160 110-200 100-140 100-200
1970-1972 Mod 120-130 80-100 100-140 100-110
1973-1976 Mod/Strong 120-150 100-170 100-150 100-150
1988-1989 Mod/Strong 40-80 70 60 60
1998-2000 Mod to Strong
40-80 40-80 40-80 40-50
2007-2008 Mod 60-70 30-50 30-40 30-50
2010-2011 Mod? ???
* Note: Streamflow % based on USGS Historical Runoff Values that are derived from streamflows
Georgia Reservoirs
La Niña and Lake Lanier Inflows
Period Type Percent of Inflow compared to Normal*
1954-1956 Mod to strong NA
1964-1965 Mod 100-140
1970-1972 Mod 75-110
1973-1976 Mod to Strong 110-150
1988-1989 Mod to Strong 40-90
1998-2000 Mod to Strong 50-60
2007-2008 Mod 50-60
2010-2011 Mod? ???
* Note: Inflows based on data from the Corps Of Engineers calculated inflow values
La Niña and Lake Lanier Inflows
La Niña and Lake Lanier Inflows
La Niña and Lake Lanier Inflows
La Niña and Lake Lanier Inflows
La Niña and Lake Lanier Inflows
La Niña and Lake Lanier Inflows
Conclusion:• Last several years…deficits in rainfall during recharge period into Summer accentuating water resource concerns• La Niña typically means lower streamflows and lower inflows in Lake Lanier but not always (likely but not 100%)• Water Supply Issues of obvious concern into 2011