March 3, 2011 Todd Shea Warning Coordination Meteorologist
National Weather Service La Crosse, WI
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Normal to above average threat for flooding on Wisconsin rivers
/ tributaries Normal to above average threat for flooding on
Wisconsin rivers / tributaries Above to Much Above Risk on
Mississippi River Above to Much Above Risk on Mississippi River
Outline Outline Setting the Stage for Potential Flooding Setting
the Stage for Potential Flooding 2011 Spring Flood Long Range
Probabilistic Outlooks 2011 Spring Flood Long Range Probabilistic
Outlooks Outlooks updated.today! Outlooks updated.today!
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Past precipitation / Antecedent soil conditions Past
precipitation / Antecedent soil conditions Snow pack / liquid
equivalent Snow pack / liquid equivalent Frost depth Frost depth
Freeze / melt cycle Freeze / melt cycle Future precipitation Future
precipitation Time of melt Time of melt Ice conditions Ice
conditions
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Factor High Risk 2011 Past Precipitation Wet Snow Pack Deep /
Wet Frost Depth Deep Melt Cycle Quick / Warm Future Precipitation
Wet Time of Melt Late Ice Conditions Thick ??? ??? ???
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Sept.23, 2010 Rainfall September 2010 Precipitation
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Fall 2010 Precipitation Fall 2010 Percent of Normal
Precipitation
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180 Day Precipitation Percent of Normal Precipitation
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Most rivers above or much above normal Reservoirs and lowland
areas are full. Reservoirs and lowland areas are full. River ice
has efficiently formed. River ice has efficiently formed. Ice jams
are possible. Ice jams are possible.
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Stage on March 1 st / Spring Crest
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TemperaturePrecipitation
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TemperaturePrecipitation
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TemperaturePrecipitation
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Minor Flood
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Moderate Flood
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Major Flood
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AHPS Webpages Soil Conditions Based on 3/3/11Soil Conditions
Based on 3/3/11 Model run from 3/7/11 6/5/11Model run from 3/7/11
6/5/11 **60 year statistical analysis does not include 2009/2010
data.**60 year statistical analysis does not include 2009/2010
data.
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Portage, WI Minor 95% (90%) - Minor Flood Stage Moderate 93%
(72%) - Moderate Flood Stage Major 78% (50%) - Major Flood Stage
**Percentages in parenthesis denote probabilistic outlooks from
2/17.
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La Crosse, WI Minor >98% (>98%) - Minor Flood Stage
Moderate >98% (95%) - Moderate Flood Stage Major 82% (59%) -
Major Flood Stage **Percentages in parenthesis denote probabilistic
outlooks from 2/17.
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Outlook Locations Categorical Flood Stages (ft) Probability
ofMinor Moderate Probability of Moderate Probability ofMajor Wisc.
Rapids Wisconsin 12/13.5/15 9% (8%)3% (3%)-- (--) Portage Wisconsin
17/18/19 95% (90%)93% (72%)78% (50%) Berlin Fox 13/14.5/15.5
>98% (75%)83% (34%)49% (19%) Afton Rock 9/11.1/12.293% (83%)49%
(39%)27% (18%) Newville Rock 10/11/11.526% (18%)1% (4%)1% (1%)
**Percentages in parenthesis denote probabilistic outlooks from
2/17 Preliminary outlooks
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Outlook Locations Categorical Flood Stages (ft) Probability
ofMinor Moderate Probability of Moderate Probability ofMajor Black
River Falls Black 47/51/55 95% (82%)80% (57%)26% (16%) La Farge
Kickapoo 12/13/1463% (24%)42% (8%)8% (1%) Viola Kickapoo
14/17/20>98% (>98%)39% (13%)1% (--) Soldiers Grove Kickapoo
13/16/19>98% (86%)34% (9%)3% (1%) Steuben Kickapoo
12/13/15>98% (>98%)>98%(63%)16% (4%) **Percentages in
parenthesis denote probabilistic outlooks from 2/17 Preliminary
outlooks
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Outlook Locations Categorical Flood Stages (ft) Probability
ofMinor Moderate Probability of Moderate Probability ofMajor Red
Wing Mississippi 14/15/16 >98% (>98%)>98% (95%)>98%
(91%) Lake City Mississippi 16/18/20 >98% (95%)88% (80%)75%
(50%) Wabasha Mississippi 12/14/16 >98% (>98%)>98%
(93%)86% (73%) Winona Mississippi 13/15/18>98% (>98%)>98%
(95%)88% (75%) La Crosse Mississippi 12/13/15.5>98%
(>98%)>98% (95%)82% (59%) **Percentages in parenthesis denote
probabilistic outlooks from 2/17 Preliminary outlooks
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Outlook Locations Categorical Flood Stages (ft) Probability
ofMinor Moderate Probability of Moderate Probability ofMajor
Lansing Mississippi 18/19/20 88% (75%)83% (65%)78% (49%) McGregor
Mississippi 16/20/23 >98% (>98%)>98% (88%)86% (67%)
Guttenberg Mississippi 15/18/21 >98% (>98%)95% (83%)78% (47%)
Dubuque Mississippi 17/18/21.5>98% (98%) 93% (78%) **Percentages
in parenthesis denote probabilistic outlooks from 2/17 Preliminary
outlooks
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Outlook Locations Categorical Flood Stages (ft) Probability
ofMinor Moderate Probability of Moderate Probability ofMajor Rock
Springs Baraboo 18.5/21/23 >98% (83%)91% (57%)37% (21%) W.
Baraboo Baraboo 9/10.5/15 50% (24%)27% (11%)4% (1%) Baraboo
16/22/23.1 >98% (83%)31% (18%)9% (8%) New Munster Fox
10/13/14>98% (96%)44% (42%)18% (18%) **Percentages in
parenthesis denote probabilistic outlooks from 2/17 Preliminary
outlooks
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Outlook Locations Categorical Flood Stages (ft) Probability
ofMinor Moderate Probability of Moderate Probability ofMajor
Watertown Rock 5.5/6/6.5 60% (32%)32% (19%)23% (9%) Jefferson Rock
10/11/13 82% (60%)60% (39%)19% (11%) Ft. Atkinson Rock 6/7/8 73%
(49%)45% (29%)1% (3%) Milford Crawfish 7/9/1063% (60%)26% (19%)8%
(13%) **Percentages in parenthesis denote probabilistic outlooks
from 2/17 Preliminary outlooks
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Additional precipitation occurs prior to the melt? Additional
precipitation occurs prior to the melt?
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Type of Melt Type of Melt Slow (optimal)- little to no
rain/snow and dryer Relative Humidity. temperatures highs mid 30s
to lower 40s, overnight lows 20s(or colder) Rapid (increases
flooding threat) Rain on snow increases melt rate and adds more
water to the situation. Temperatures Highs mid 40s and warmer, lows
around 30 and warmer (Colder overnight lows slows down or shuts off
the melting process) A delayed thaw increases the possibility of a
faster melt and the likelihood that a rain on snow event would
occur.
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Location (lat and lon if available otherwise, general
description, bridge, river, etc) Location (lat and lon if available
otherwise, general description, bridge, river, etc) Duration if
known Duration if known Is water rising behind the jam (quickly??)
Is water rising behind the jam (quickly??) Is water moving around
the sides of the jam? Is water moving around the sides of the jam?
Is anything flooding/near to being flooded? Is anything
flooding/near to being flooded? Is it a sheet of ice, lots of large
ice chunks. Is it a sheet of ice, lots of large ice chunks. Is the
ice moving, lifting, etc Is the ice moving, lifting, etc What
infrastructure is immediately downstream? What infrastructure is
immediately downstream? Estimate of the size or length of the jam.
Estimate of the size or length of the jam. Ice Information to
Report to the NWS
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In addition to the traditional methods of NOAA Weather Radio,
Internet, TV and Radio.
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RSS (Really Simple Syndication) Feeds are sent for River
Information including River Observations River Observations
Issuance of River forecasts Issuance of River forecasts When
Critical alert stages are exceeded or forecast When Critical alert
stages are exceeded or forecast Main AHPS RSS feed page:
http://www.weather.gov/ahps/rsshttp://www.weather.gov/ahps/rss Main
NWS RSS feed page at:
http://www.weather.gov/rsshttp://www.weather.gov/rss
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Main iNWS website to register http://inws.wrh.noaa.gov/ AHPS
Mobile Website - http://ahpsmobile.wrh.noaa.gov/
http://ahpsmobile.wrh.noaa.gov/
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https://nwschat.weather.gov/
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Minor to Moderate Flooding in some Wisconsin Rivers Minor to
Moderate Flooding in some Wisconsin Rivers Moderate to Major
Flooding certainly possible along Mississippi River Moderate to
Major Flooding certainly possible along Mississippi River Optional
Spring Flood Outlook: March 10th