CPC Monthly Climate Review
September 2014
Yan Xue Outline:
1. Global Patterns
2. Tropical Climate Variability
ENSO, MJO, IOD, TAV, Hurricane Season 3. Extra-Tropical Climate Variability
PDO, NAO, Asia and N. America Monsoons, Ozone Hole
4. U.S. Climate, Outlooks and Verifications
Thanks to Anthony Artusa, Mingyue Chen/Wanqiu Wang, Wei Shi, Kingtse Mo, Craig Long,
Pingping Xie, Muthu Chelliah, Caihong Wen, Michelle L’Heureux, Jon Gottschalck, Jae Schemm
1. Global Patterns
SST Anomaly (
0C) and Anomaly Tendency
http://www.cpc.ncep.noaa.gov/products/GODAS/ocean_briefing.shtml DMI= -0.5
PDO= +0.74
ENSO-neutral NINO3.4=+0.47 MDR near-normal
cooling
Upper 300m Heat Content Anomaly (
0C) and Anomaly Tendency
http://www.cpc.ncep.noaa.gov/products/GODAS/multiora_body.html -DMI
Not clear +PDO pattern
Favourable for El Nino
N. Atlantic below-normal Unfavourable for hurricane E. Pac. above-normal
favourable for hurricane
Longitude-Depth Temperature Anomaly and Anomaly Tendency in 1
OS-1
ON
http://www.cpc.ncep.noaa.gov/products/GODAS/multiora_body.html
Sea Surface Salinity (SSS) and E-P Anomaly
From Pingping Xie enhanced
precipitation
enhanced
precipitation
ENSO
2. Tropical Climate Variability
SST Indices
SOI < 0: El Nino-Like
OLR < 0: El Nino-Like OLR > 0: La Nina-Like u850 < 0: El Nino favorable
u850 > 0: La Nina favorable
SOI, Winds and OLR Indices
Weekly ENSO Update
http://www.cpc.ncep.noaa.gov/products/pr
ecip/CWlink/MJO/enso.shtml
Depth of 20C Isotherm Anomaly (2S-2N, GODAS)
850mb Zonal Wind Anomaly
(5S-5N, NCEP R1)
SST Anomaly (2S-2N)
Sea Surface Salinity Anomaly
(5S-5N)
Tropical Pacific
Observing System
Real-Time Multiple Ocean Reanalysis Intercomparison
(http://www.cpc.ncep.noaa.gov/products/GODAS/multiora_body.html)
Upper 300m Heat Content Anomaly (1981-2010 Clim.)
Warm Water Volume Index Derived
From Ensemble Mean of Ocean Reanalyses
- Warm Water Volume averaged in Aug-Sep 2014 is similar to that in Aug-Sep of 1991, 2004, 2006, 2009.
AS 82 AS 97 AS 14
AS 02
AS 91 AS 06 AS 09
AS 86
AS 04
86/87 91/92 94/95
06/07 09/10
Upper 300m Heat Content Anomaly Averaged in 1S-1N
12/13 14/15
04/05
19
NINO3.4 Forecast Plums
MJO
2. Tropical Climate Variability
OLR Anomalies – Past 30 days
Drier-than-normal conditions, positive OLR anomalies (yellow/red shading) Wetter-than-normal conditions, negative
OLR anomalies (blue shading)
From late August to early September, enhanced (suppressed) convection was observed near India and Central America (equatorial Indian Ocean).
During mid-September, enhanced
convection was located over Southeast Asia and Central America, while the area of suppressed convection expanded near the Date Line.
During mid-September, monsoon flow over the Bay of Bengal and Southeast Asia
waned. Anomalous convection over Central America shifted northward with some areas of suppressed convection evident over the eastern Pacific.
Outgoing Longwave Radiation (OLR) Anomalies (2.5°N-17.5°N)
Drier-than-normal conditions, positive OLR anomalies (yellow/red shading)
Wetter-than-normal conditions, negative OLR anomalies (blue shading)
(Courtesy of CAWCR Australia Bureau of Meteorology)
Time
Longitude
Since April, enhanced convection has propagated slowly eastward from the Maritime Continent to the central Pacific (red box).
The MJO became more coherent during April, with the subseasonal envelopes of enhanced and suppressed convection modulating the strength of the low frequency signal. The anomalous tropical convection pattern became largely incoherent during mid-May. During June, the MJO became more organized, primarily over the Indian Ocean, but the pattern became less coherent with respect to canonical MJO activity through August.
There is evidence of westward-moving subseasonal variability from mid-August and later. Recently, anomalous convection has increased near 150E while waning over the eastern Pacific.
200-hPa Velocity Potential Anomalies (5°S-5°N)
Positive anomalies (brown shading) indicate unfavorable conditions for precipitation Negative anomalies (green shading) indicate favorable conditions for precipitation
Time
Longitude
A slow eastward progression of negative anomalies was observed from March to present across the Indo-Pacific warm pool and central Pacific (red box).
During March through April, anomalies
propagated eastward with time associated with the MJO before weakening for much of May.
The pattern became more organized during June with a more coherent wave-1 MJO-like structure with eastward propagation.
The pattern became less coherent during early July, but then organized again in late July and August, with a wide area of suppressed convection moving around the planet.
During mid-September, anomalies were generally small with positive (negative) anomalies over the eastern Pacific (over the Indian Ocean and near 150E).
IOD, TAV, Hurricane
2. Tropical Climate Variability
Evolution of Indian Ocean SST Indices
Fig. I1a. Indian Ocean Dipole region indices, calculated as the area-averaged monthly mean sea surface temperature anomalies (OC) for the SETIO [90ºE-110ºE, 10ºS-0] and WTIO [50ºE-70ºE, 10ºS-10ºN]
regions, and Dipole Mode Index, defined as differences between WTIO and SETIO. Data are derived from the NCEP OI SST analysis, and anomalies are departures from the 1981-2010 base period means.
- Negative DMI persisted in September.
Evolution of Tropical Atlantic SST Indices
Fig. A1a. Tropical Atlantic Variability region indices, calculated as the area-averaged monthly mean sea surface temperature anomalies (ºC) for the TNA [60ºW-30ºW, 5ºN-20ºN], TSA [30ºW-10ºE, 20ºS-0] and ATL3 [20ºW-0, 2.5ºS-2.5ºN] regions, and Meridional Gradient Index, defined as differences between TNA and TSA. Data are derived from the NCEP OI SST analysis, and anomalies are departures from the 1981-2010 base period means.
-TNA – TSA gradient index has been below-normal since Feb 2014, unfavourable for hurricane activity.
2014 Atlantic Hurricane Counts
(http://weather.unisys.com/hurricane)
- Atlantic Outlook (Aug update, 70% above-normal):
7-12 Named Storms (12 average) 3-6 Hurricanes (6 average)
0-2 Major Hurricanes (3 average) 40%-90% ACE
- Atlantic Counts by Oct 6:
5 Named Storms 4 Hurricanes
1 Major Hurricanes 41% ACE
- Only three seasons since 1995 were below normal (1997, 2009, and 2013).
- If the current outlook verifies, 2014 will become the fourth below-normal season since 1995.
- It would mark the first
time since 1995 that two
consecutive seasons
were below-normal.
- E. Pacific Counts by Oct 6:
19 Named Storms 14 Hurricanes
5 Major Hurricanes 142% ACE
2014 E. Pacific Hurricane Counts
(http://weather.unisys.com/hurricane)
- E. Pacific Outlook (50% above-normal):
14-20 Named Storms (15 average)
7-11 Hurricanes (8 average)
3-6 Major Hurricanes (4 average) 95%-160% ACE
Last Three Month SST, OLR and 925hp Wind Anom.
3. Extra-Tropical Climate Variability
PDO, NAO, Monsoons, Ozone Hole,
PDO index
- Pacific Decadal Oscillation is defined as the 1st EOF of monthly ERSST v3b in the North Pacific for the period 1900- 1993. PDO index is the standardized projection of the monthly SST anomalies onto the 1st EOF pattern.
- The PDO index differs slightly from that of JISAO, which uses a blend of UKMET and OIv1 and OIv2 SST.
- PDO index enhanced in Sep with PDO index
=+0.74
NAO and SST Anomaly in North Atlantic
Fig. NA2. Monthly standardized NAO index (top) derived from monthly standardized 500-mb height anomalies obtained from the NCEP CDAS in 20ºN-90ºN (http://www.cpc.ncep.noaa.gov). Time-Latitude section of SST anomalies averaged between 80ºW and 20ºW (bottom). SST are derived from the NCEP OI SST analysis, and anomalies are departures from the 1981-2010 base period means.
- NAO index switched to a strong positive phase , with NAO index= in September 2014.
- Large positive SST anomaly presented near the east coast of Canada and Norwegian Sea.
- High-latitude North Atlantic SSTA are reversely related to NAO index (negative NAO coincides with SST warming).
Rainfall Anomaly Patterns
Hurricane Odile (Sept 10-17) contributed significant rainfall to Southwest US and Northwest Mexico in September.
Overall for the NAM region during JAS: near to above-average in the northern part but dry in the south.
September 2014 JAS 2014
From Wei Shi
Seasonal Evolution: Rainfall
From Wei Shi
Category 4 hurricane Odile
India Met. Dept. (IMD) Forecast:
Rainfall over the country as a whole for the 2014 southwest monsoon season (June-September)
is likely to be below normal (90-96%
of normal).
OBSERVED: INDIA 2014 SUMMER MONSOON SEASON (1 June – 30 September) 12% BELOW NORMAL
From Muthu
From Craig
4. U.S. Climate (drought),
Outlooks and Verifications
U.S. Temperature and Precipitation Departures During U.S. Temperature and Precipitation Departures During
the Last 30 Days the Last 30 Days
End Date: 27 September 2014
Percent of Average
Precipitation Temperature Departures
(degree C)
1 of 2
SST along N. America Coast
DROUGHT MONITOR
S LS LS LS S S LLLS LS LS LS S S S LS S S S S S S S S S S LS LS LS LS S LLS LS LS LS S S S LS S S S S S S S S S S S S L
T heD roughtM onitorfocusesonbroad-scaleconditions.Localconditionsm ayvary.S eeaccom panyingtextsum m aryforforecaststatem ents.
L h ttp ://d rough tm on ito r.un l.edu
/ U
.S .D roughtM onito r
Ju ly29 ,2014
V alid8a.m .E D T (R eleasedT hursday,Jul.31,2014)Intensity:
D 0A bnorm allyD ryD 1M oderateD roughtD 2S evereD roughtD 3E xtrem eD roughtD 4E xceptionalD rought
A uthor:B radR ippeyD roughtIm pactT ypes:
S
= S hort-T erm ,typicallylessthan6m onths(e.g.agriculture,grasslands)L=
Long-T erm ,typicallygreaterthan6m onths(e.g.hydrology,ecology)D elineatesdom inantim pacts
U .S .D epartm entofA gricultur e
- Low water levels are visible
at the Almaden Reservoir on
January 28, 2014 in San
Jose, Calif.
46
Streamflow Percentiles (USGS)
Dryness: California, Texas
Texas drought improved
Wetness: Dakotas , Minn, Wisconsin, Missouri basin, Great Lakes
July 2014 AUG
Sep
From Kingtse Mo
California Reservoir Conditions
47
Most reservoirs are only 11-30% capacity
From Kingtse Mo
Oct 2014 Outlook
OND 2014 Outlook
Thanks!
Global Temperatures
Global Precipitation
U.S. Temperature and Precipitation Departures During the U.S. Temperature and Precipitation Departures During the
Last 30 Days Last 30 Days
End Date: 4 October 2014
Percent of Average
Precipitation Temperature Departures
(degree C)
1 of 2
U.S. Temperature and Precipitation Departures During the U.S. Temperature and Precipitation Departures During the
Last 90 Days Last 90 Days
End Date: 4 October 2014
Percent of Average
Precipitation Temperature Departures
(degree C)
2 of 2
Monsoon precip
59
