Friday Weather Discussion Clark Evans 27 March 2015

Friday Weather Discussion

Clark Evans27 March 2015

MJO Phase Diagram

Peak amplitude on record (1974-present): 4.265

http://cawcr.gov.au/staff/mwheeler/maproom/RMM/

MJO & Tropical Wave Evolution

http://cawcr.gov.au/staff/mwheeler/maproom/OLR_modes/index.htm

OLR: MJO and Anomaly

http://cawcr.gov.au/staff/mwheeler/maproom/RMM/

850/200 hPa u: MJO and Anomaly

850 hPa at left, 200 hPa at right. http://cawcr.gov.au/staff/mwheeler/maproom/RMM/

850 hPa u: Full, Anomaly

Full field at left, anomaly (from 1989-2008 climo) field at right.http://www.atmos.albany.edu/student/carl/weather/

Equatorial Pacific Ocean State

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/enso.shtmlhttp://www.ncdc.noaa.gov/teleconnections/enso/indicators/sea-temp.php

ENSO Forecasts

http://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/

“…the dynamical models are anticipating a moderately strong event to develop in the Northern Hemisphere’s late spring and summer. They are notoriously bad for seeing through the spring predictability barrier, though, so it should be noted that the statistical models are more conservative, predicting a neutral-to-weak El Niño event.”

IRI March 2015 Climate Briefing, http://iri.columbia.edu/news/march-2015-el-nino/

April-May-June 2015 Forecasts

http://iri.columbia.edu/our-expertise/climate/forecasts/seasonal-climate-forecasts/

Winter 2014-15 In Review

Dec 2014 – Feb 2015 Temperature

http://www.ncdc.noaa.gov/temp-and-precip/global-maps/

Dec 2013 – Feb 2014 Temperature

http://www.ncdc.noaa.gov/temp-and-precip/global-maps/

Dec 2014 – Feb 2015 Temperature

http://www.ncdc.noaa.gov/temp-and-precip/us-maps/

Dec 2014 – Feb 2015 Temperature

http://mrcc.isws.illinois.edu/CLIMATE/Maps/map_btd.jsp

Dec 2014 – Feb 2015 Precipitation

http://www.ncdc.noaa.gov/temp-and-precip/us-maps/

Dec 2014 – Mar 2015 Precipitation

http://mrcc.isws.illinois.edu/CLIMATE/Maps/map_btd.jsp

Dec 2014 – Mar 2015 Snowfall

http://mrcc.isws.illinois.edu/CLIMATE/Maps/map_btd.jsp

Drought Monitor

http://droughtmonitor.unl.edu/

500 hPa Height, Anomaly

Derived from NCEP-NCAR Reanalysis, 1 December 2014 – 23 March 2015http://www.esrl.noaa.gov/psd/data/composites/day/

850 hPa Temperature, Anomaly

Derived from NCEP-NCAR Reanalysis, 1 December 2014 – 23 March 2015http://www.esrl.noaa.gov/psd/data/composites/day/

Five Periods of Interest

• 5-27 December (warm)

• 29 December – 14 January (cold)

• 15-31 January (warm)

• 1 February – 6 March (cold)

• 8-20 March (warm)

A Mild December

http://mrcc.isws.illinois.edu/CLIMATE/Maps/map_btd.jsp

A Mild December

Derived from NCEP-NCAR Reanalysis, 5-27 December 2014http://www.esrl.noaa.gov/psd/data/composites/day/

A Chilly New Year

http://mrcc.isws.illinois.edu/CLIMATE/Maps/map_btd.jsp

A Chilly New Year

Derived from NCEP-NCAR Reanalysis, 29 December 2014 – 14 January 2015http://www.esrl.noaa.gov/psd/data/composites/day/

Warmer and Dry in Late January

http://mrcc.isws.illinois.edu/CLIMATE/Maps/map_btd.jsp

Warmer and Dry in Late January

Derived from NCEP-NCAR Reanalysis, 15-31 January 2015http://www.esrl.noaa.gov/psd/data/composites/day/

A Persistent Mid-Winter’s Chill

http://mrcc.isws.illinois.edu/CLIMATE/Maps/map_btd.jsp

A Persistent Mid-Winter’s Chill

Derived from NCEP-NCAR Reanalysis, 1 February to 6 March 2015http://www.esrl.noaa.gov/psd/data/composites/day/

Spring into March

http://mrcc.isws.illinois.edu/CLIMATE/Maps/map_btd.jsp

Spring into March

Derived from NCEP-NCAR Reanalysis, 8-20 March 2015http://www.esrl.noaa.gov/psd/data/composites/day/

Possible Pattern Influences

http://cawcr.gov.au/staff/mwheeler/maproom/RMM/phase.Last90days.htmlhttp://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/Composites/Temperature/

Possible Pattern Influences

http://www.cpc.noaa.gov/products/precip/CWlink/daily_ao_index/ao_index.html

Possible Pattern Influences

http://www.cpc.noaa.gov/products/precip/CWlink/daily_ao_index/loading.htmlhttp://www.atmos.albany.edu/student/heathera/2015.html

SLP’ -

SLP’ +

SLP’ +

SLP’ -

Possible Pattern Influences

http://www.cpc.noaa.gov/products/precip/CWlink/daily_ao_index/loading.htmlhttp://www.atmos.albany.edu/student/heathera/2015.html

SLP’ -

SLP’ +

SLP’ +

SLP’ -

Possible Pattern Influences

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/teleconnections.shtml

+NAO very similar to +AO during boreal

winter

+PNA in winter: below- (above-) normal heights in C. Pacific (western N.

America).

Possible Pattern Influences

http://cawcr.gov.au/staff/mwheeler/maproom/RMM/http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/enso.shtml

Some Scientific Questions

• Why does the spring predictability barrier for ENSO exist, and will the current El Niño intensify or not?

• Why has anomalous cold occurred over North America and nowhere else in the last two winters?

• Why did the mid-latitude pattern evolve as it did on sub-seasonal scales? Can we even identify why?

• What caused the MJO to achieve such a high amplitude this March, and what does it mean?