CariCOF Climate Outlook December 2014/January-February 2015 and March-April-May 2015 Coordination – CIMH – Dr. Cédric J. Van Meerbeeck Participating territories Antigua & Barbuda, Aruba, Bahamas, Barbados, Belize, Cayman Islands, Cuba, Curaçao, Dominica, Dominican Republic, French Guiana, Grenada, Guadeloupe, Guyana, Haïti, Jamaica, Martinique, Puerto Rico, St. Barth’s, St. Kitts & Nevis, St. Lucia, St. Maarten/St. Martin, St. Vincent & the Grenadines, Suriname, Trinidad & Tobago and the US Virgin Islands

XLII FCAC – Ciudad de Guatemala, 09/ Regional Climate Outlook Forums CariCOF - FCAC 2 CariCOF FCAC

RAINFALL

DJF rainfall

CPT probabilistic DJF rainfall forecast CCA experiments: 1) Predictor is observed SST over the tropical Atlantic and Pacific over October (data source: NOAA ERSSTv3b, obtained from the IRI data library) 2) Predictor is observed SST over the tropical North Atlantic over October 3) Predictor is predicted SST over the tropical Atlantic and Pacific over DJF (data source: NOAA CPC CFSv2, October initialisation) 4) Predictor is predicted SST over the tropical North Atlantic 5) Predictor is predicted rainfall totals over the Caribbean (data source: ECHAM4.5 ensemble24, obtained from the IRI data library) Besides the major control of ENSO (here represented by Pacific tropical SST anomalies) and tropical north Atlantic SSTs on Caribbean rainfall variability, these experiments take the contrast between Pacific and Caribbean/trop. N Atlantic SSTs into account, as those factors are regarded as the most important drivers of rainfall throughout the Caribbean.

Experiment 1

CPT rainfall forecast Data: Predictor = October SST observations E-20W and 30N-20S (i.e. Tropical Pacific & Atlantic) [Source: ERSSTv3b, from IRI data library] Predictand = DJF rainfall for 165 Caribbean stations Parameters: CCA modes: max = 5; optimum = 1 X modes: max = 8; optimum = 1 Y modes: max = 8; optimum = 2 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 150 stations included in hindcast and forecast Goodness index (transformed Y) = !0.165 Limited!

ROC area maps

CCA modes

Experiment 1 DJF Rainfall Forecast Tercile maps NORMAL BELOW ABOVE

Experiment 2

CPT rainfall forecast Data: Predictor = August SST observations W and 0-30N (i.e. tropical N Atl.) [Source: ERSSTv3b, from IRI data library] Predictand = DJF rainfall for 165 Caribbean stations Parameters: CCA modes: max = 5; optimum = 1 X modes: max = 8; optimum = 5 Y modes: max = 8; optimum = 5 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 150 stations included in hindcast and forecast Goodness index (transformed Y) = !0.198 Limited!

ROC area maps

CCA modes

Experiment 2 DJF Rainfall Forecast Tercile maps NORMAL BELOW ABOVE

Experiment 3

CPT rainfall forecast Data: Predictor = DJF simulated SST E-20W and 30N-20S (i.e. tropical Pacific & Atlantic) [Source: NOAA CPC – CFSv2, August initialisation] Predictand = DJF rainfall for 165 Caribbean stations Parameters: CCA modes: max = 5; optimum = 1 X modes: max = 8; optimum = 6 Y modes: max = 8; optimum = 2 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 151 stations included in hindcast and forecast Goodness index (transformed Y) = Moderate

ROC area maps

CCA modes

Experiment 3 DJF Rainfall Forecast Tercile maps BELOW ABOVE NORMAL

Experiment 4

CPT rainfall forecast Data: Predictor = DJF simulated SST 90-20W and 0-30N (i.e. tropical N Atl.) [Source: NOAA CPC – CFSv2, August initialisation] Predictand = DJF rainfall for 165 Caribbean stations Parameters: CCA modes: max = 5; optimum = 1 X modes: max = 8; optimum = 5 Y modes: max = 8; optimum = 1 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 151 stations included in hindcast and forecast Goodness index (transformed Y) = !0.181 Limited!

ROC area maps

CCA modes

Experiment 4 DJF Rainfall Forecast Tercile maps NORMAL BELOW ABOVE

Experiment 5

CPT rainfall forecast Data: Predictor = DJF simulated rainfall W and 5S-35N (i.e. broader Caribbean) [Source: ECHAM4.5 ensemble 24 – from IRI data library] Predictand = DJF rainfall for 165 Caribbean stations Parameters: CCA modes: max = 5; optimum = 2 X modes: max = 5; optimum = 4 Y modes: max = 5; optimum = 2 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 150 stations included in hindcast and forecast Goodness index (transformed Y) = !0.190 Limited!

ROC area maps

CCA modes

Experiment 5 DJF Rainfall Forecast Tercile maps NORMAL BELOW ABOVE

MAM rainfall

CPT probabilistic MAM rainfall forecast CCA experiments: Oct 1) Predictor is observed SST over the tropical Atlantic and Pacific over Oct (data source: NOAA ERSSTv3b, obtained from theIRI data library) MAM 2) Predictor is predicted SST over the tropical Atlantic and Pacific over MAM (data source: NOAA CPCFSv2, Oct(initialisation)

Experiment 1

CPT MAM rainfall forecast Data: Oct Predictor = Oct SST observations E-20W and 30N-20S (i.e. tropical Pacific & Atlantic) [Source: ERSSTv3b, from IRI data library] Predictand = MAM rainfall for 165 Caribbean stations Parameters: CCA modes: max = 5; optimum = 1 X modes: max = 8; optimum = 8 Y modes: max = 8; optimum = 5 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 121 stations included in hindcast and forecast Goodness index (transformed Y) = !! Very Limited! !

ROC area maps

CCA modes

Experiment 1 MAM Rainfall Forecast Tercile maps NORMAL BELOW ABOVE

Experiment 2

CPT MAM rainfall forecast Data: MAM Predictor = MAM simulated SST E-20W and 30N-20S (i.e. tropical Pacific & Atlantic) [Source: NOAA CPC – CFSv2, Nov initialisation] Predictand = MAM rainfall for 165 Caribbean stations Parameters: CCA modes: max = 5; optimum = 1 X modes: max = 8; optimum = 1 Y modes: max = 8; optimum = 1 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 153 stations included in hindcast and forecast Goodness index (transformed Y) = !! Very Limited!!

ROC area maps

CCA modes

Experiment 2 MAM Rainfall Forecast Tercile maps NORMAL BELOW ABOVE

Supporting probabilistic rainfall forecasts CARICOF national/sub-regional objective forecasts & outlook guidance: 1)Puerto Rico & USVI:DJFA = % ; N = % ; B = % MAMA = % ; N = % ; B = % Note: 2)Guadeloupe:DJFA = 35% ; N = 35% ; B = 30% Martinique :DJFA = 32% ; N = 36% ; B = 32% French Guiana:DJFA = 30% ; N = 36% ; B = 34% French Northern Antilles:DJFA = 32% ; N = 35% ; B = 33% Note: For the Lesser Antilles there is an agreement between several dynamic models (Eurosip, JMA) ) and statistic SST/RR (with skill) for a normal forecast in DJF (predictor stay SST over tropical North Atlantic and Pacific, with a low but positive ENSO anomaly). Over French Guiana : The statistic model has good skill and says normal or above. The dynamic models exhibit a drier than normal forecast. Over ASO, the drought situation was: Normal on St. Barth’s and dry in St. Martin, normal to dry in Guadeloupe, normal (windward side) to very dry (leeward side) in Martinique. Normal to wet conditions in French Guiana. 3)Barbados:DJFA = 30%; N = 39% ; B = 31% MAMA = 62%; N = 20% ; B = 18% Note: CPT CCA with ERRSTs and CFSv2 SSTs showed good skill and fair discrimination for DJF, very limited skill and poor discrimination for MAM. 4)St. Maarten & NE Caribb.:DJFA = 37%; N = 32% ; B = 31% Note: CPT CCA with ERRSTs and CFSv2 SSTs showed (very) limited skill and very poor discrimination for DJF

Supporting probabilistic rainfall forecasts CARICOF national/sub-regional objective forecasts & outlook guidance: 5)Trinidad and Tobago:DJFA = 53% ; N = 31% ; B = 16% MAMA = % ; N = % ; B = % Note:CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed fair skill and no to good discrimination for DJF. 6)Jamaica:DJFA = 29% ; N = 22% ; B = 49% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed limited to moderate skill and no to good discrimination for DJF. 7)Suriname:DJFA = 65% ; N = 25% ; B = 10% MAMA = 40% ; N = 30% ; B = 30% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed fair to good skill and limited to fair discrimination for DJF, limited skill and discrimination for MAM. 8)Belize:DJFA = 57% ; N = 23% ; B = 20% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed limited skill and no to fair discrimination for DJF. 9)St. Vincent:DJFA = 50% ; N = 30% ; B = 20% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed moderate skill and discrimination for DJF. 10)Curaçao:ASOA = % ; N = % ; B = % Note:

Supporting probabilistic rainfall forecasts CARICOF national/sub-regional objective forecasts & outlook guidance : 11)Grenada:DJFA = 44% ; N = 33% ; B = 23% MAMA = 41% ; N = 30% ; B = 29% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed moderate to fair skill and limited to moderate discrimination for DJF, negative skill and no discrimination for MAM. 12) Aruba:DJFA = 65% ; N = 24% ; B = 11% *** Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed fair skill and moderate to fair discrimination for DJF.***After multi-model ensemble: A40 N35 B25. 13) St. Lucia:DJFA = 33% ; N = 33% ; B = 33% MAMA = 32% ; N = 32% ; B = 36% Note: CPT CCA experiments using ERSSTv3b showed limited skill and limited discrimination for DJF, negative skill and no discrimination for MAM. 14) Cayman:DJFA = 12% ; N = 22% ; B = 66% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed limited skill and no to moderate discrimination. 15) Dominica:DJFA = 46% ; N = 19% ; B = 35% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed limited to fair skill and no to good discrimination. 16) Guyana:DJFA = % ; N = % ; B = % Note: 17) Antigua:DJFA = 48% ; N = 29% ; B = 23% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed very limited to fair skill and no to moderate discrimination.

Supporting probabilistic rainfall forecasts CARICOF national/sub-regional objective forecasts & outlook guidance : 18)St. Kitts:DJFA = 62% ; N = 26% ; B = 12% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed very limited to fair skill and no to moderate discrimination. 19)Bahamas:DJFA = 25% ; N = 15% ; B = 59% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed negative (ERSST) to fair (CFSv2) skill and no (ERSST) to moderate (CFSv2) discrimination. 20)Cuba - West:DJFA = 26% ; N = 35% ; B = 39% Cuba - Central:DJFA = 24% ; N = 36% ; B = 40% Cuba - East:DJFA = 40% ; N = 20% ; B = 41% Note: CPT CCA experiments using ERSSTv3b and CFSv2 SSTs showed limited (ERSST) to fair (CFSv2) skill and no to moderate discrimination.

CariCOF CPT output (background) and National/sub-regional rainfall outlooks

CariCOF precipitation outlooks

Supporting probabilistic precipitation forecasts Eight data sources (incl. GPCs): 1)IRI multi-model probability forecast (only multi-model forecast that recalibrates & weights the models based on past performance); 2)UK Met Office GCM (UKMO) probability forecast; 3)European Center for Mid-range Weather Forecast GCM (ECMWF) and EUROSIP (multi-model) probability forecasts; 4)APEC Climate Center (APCC) multi=model probability forecasts; 5)WMO Lead Centre for LRF – MME. 6)CFSv2 model 7)MétéoFrance Arpège model. 8)JMA model Rainfall outlooks are generated next to T 2m outlooks (see Appendix). Rainfall tendencies from supporting models and local expertise: 1)ENSO conditions have recently been (warm-)neutral (SST anom °C). Most new model runs suggest a progression into an El Niño by NDJ 2014, with an estimated overall confidence of 67% for NDJ and 58-66% for FMA. Similarly, SSTs are slightly above average around N and E of the Caribbean, as well as further out eastward in the N Atlantic. However, this marks a small reversal in anomalies compared to previous months and may be (partly) due to weaker trade winds.associated with an unusual northward excursion of the ITCZ in late September and the first half of October as well as two periods of negative NAO. Into FMA, indications are that eastern portions of the Tropical North Atlantic could return to average SSTs. 2)Thanks to slightly warmer SSTs around the Atlantic during NDJ, average to above-average air moisture may be the prevalent pattern, marking a shift from a pattern of drier air observed during much of the year. Further, the suggested weak El Niño may sustain increased vertical wind shear over the tropical North Atlantic as well as over eastern and southern Caribbean (including the Guianas). 3)The signals of added moisture, but possibly stronger wind shear will counteract each other in producing anomalous rainfall. Testimony to the uncertainty as to which factor will dominate is the disagreement between some global models as to NDJ rainfall, with some suggesting below- to normal over the E Caribbean, and others rather above-normal.

DRAFT Probabilistic DJF rainfall forecast map DRAFT

Probabilistic MAM rainfall forecast map DRAFT

2m TEMPERATURE

DJF

CPT probabilistic DJF 2m temp. forecast CCA experiments: 1) Predictor is observed SST over the tropical Atlantic and Pacific over October (data source: NOAA ERSSTv3b, obtained from the IRI data library) 2) Predictor is observed SST over the tropical North Atlantic over October 3) Predictor is predicted SST over the tropical Atlantic and Pacific over DJF (data source: NOAA CPC CFSv2, November initialisation) 4) Predictor is predicted SST over the tropical North Atlantic over DJF 5) Predictor is predicted T2m over the Caribbean over DJF (data source: ECHAM4.5 ensemble24, obtained from the IRI data library)

Experiment 1

CPT T2m forecast Data: Predictor = October SST observations E-20W and 30N-20S (i.e. Tropical Pacific & Atlantic) [Source: ERSSTv3b, from IRI data library] Predictand = DJF T2m for 51 Caribbean stations Parameters: CCA modes: max = 5; optimum = 2 X modes: max = 8; optimum = 2 Y modes: max = 8; optimum = 6 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 36 stations included in hindcast and forecast Goodness index (transformed Y) = Fair

ROC area maps

CCA modes

Experiment 1 DJF T2m Forecast Tercile maps NORMAL BELOW ABOVE

Experiment 2

CPT T2m forecast Data: Predictor = October SST observations W and 0- 30N (i.e. tropical N Atl.) [Source: ERSSTv3b, from IRI data library] Predictand = DJF T2m for 51 Caribbean stations Parameters: CCA modes: max = 5; optimum = 4 X modes: max = 8; optimum = 5 Y modes: max = 8; optimum = 7 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 36 stations included in hindcast and forecast Goodness index (transformed Y) = Fair

ROC area maps

CCA modes

Experiment 2 DJF T2m Forecast Tercile maps NORMAL BELOW ABOVE

Experiment 3

CPT T2m forecast Data: Predictor = DJF simulated SST E-20W and 30N-20S (i.e. tropical Pacific & Atlantic) [Source: NOAA CPC – CFSv2, Nov initialisation] Predictand = DJF T2m for 51 Caribbean stations Parameters: CCA modes: max = 5; optimum = 2 X modes: max = 8; optimum = 2 Y modes: max = 8; optimum = 4 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 36 stations included in hindcast and forecast Goodness index (transformed Y) = Moderate

ROC area maps

CCA modes

Experiment 3 DJF T2m Forecast Tercile maps NORMAL BELOW ABOVE

Experiment 4

CPT T2m forecast Data: Predictor = DJF simulated SST 90-20W and 0-30N (i.e. tropical N Atl.) [Source: NOAA CPC – CFSv2, Nov initialisation] Predictand = DJF T2m for 51 Caribbean stations Parameters: CCA modes: max = 5; optimum = 5 X modes: max = 8; optimum = 5 Y modes: max = 8; optimum = 6 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 36 stations included in hindcast and forecast Goodness index (transformed Y) = Moderate

ROC area maps

CCA modes

Experiment 4 DFJ T2m Forecast Tercile maps NORMAL BELOW ABOVE

Experiment 5

CPT T2m forecast Data: Predictor = DJF simulated T2m W and 5S-35N (i.e. broader Caribbean) [Source: ECHAM4.5 ensemble 24 – from IRI data library] Predictand = DJF T2m for 51 Caribbean stations Parameters: CCA modes: max = 3; optimum = 2 X modes: max = 5; optimum = 3 Y modes: max = 5; optimum = 3 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 36 stations included in hindcast and forecast Goodness index (transformed Y) = !Limited!

ROC area maps

CCA modes

Experiment 5 DJF T2m Forecast Tercile maps NORMAL BELOW ABOVE

MAM T2m

CPT probabilistic MAM 2m temp. forecast CCA experiments: OCT 1) Predictor is observed SST over the tropical Atlantic and Pacific over OCT (data source: NOAA ERSSTv3b, obtained from theIRI data library) MAM 2) Predictor is predicted SST over the tropical Atlantic and Pacific over MAM (data source: NOAA CPCFSv2, November (initialisation)

Experiment 1

CPT MAM T2m forecast Data: OCTOBER Predictor = OCTOBER SST observations E-20W and 30N-20S (i.e. tropical Pacific & Atlantic) [Source: ERSSTv3b, from IRI data library] Predictand = MAM T2m for 51 Caribbean stations Parameters: CCA modes: max = 5; optimum = 2 X modes: max = 8; optimum = 2 Y modes: max = 8; optimum = 4 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 36 stations included in hindcast and forecast Goodness index (transformed Y) = Good

ROC area maps

CCA modes

Experiment 1 MAM T2m Forecast Tercile maps NORMAL BELOW ABOVE

Experiment 2

CPT MAM T2m forecast Data: MAM Predictor = MAM simulated SST E-20W and 30N-20S (i.e. tropical Pacific & Atlantic) [Source: NOAA CPC – CFSv2, Nov initialisation] Predictand = MAM T2m for 51 Caribbean stations Parameters: CCA modes: max = 5; optimum = 2 X modes: max = 8; optimum = 5 Y modes: max = 8; optimum = 4 Missing Y data threshold: 20% missing values, 10% missing stations, leading to 36 stations included in hindcast and forecast Goodness index (transformed Y) = Good

ROC area maps

CCA modes

Experiment 2 MAM T2m Forecast Tercile maps NORMAL BELOW ABOVE

Supporting probabilistic T 2m forecasts CARICOF national/sub-regional objective forecasts & outlook guidance: 1)Cayman:DJFA = 82% ; N = 10% ; B = 8% Note: CPT CCA with ERSSTv3b & CFSv2 SSTs showed limited to fair skill and moderate to fair discrimination. Temperature will continue to be above normal. 2)St. Lucia:DJFA = 60% ; N = 30% ; B = 10% MAMA = 75% ; N = 20% ; B = 5% Note: CPT CCA with ERSSTv3b showed good skill and fair to good discrimination for DJF and MAM. 3)Puerto Rico & USVI:DJFA = % ; N = % ; B = % MAMA = % ; N = % ; B = % Note: 4)St. Maarten & NE Caribb:DJFA = 49%; N = 36% ; B = 15% Note:CPT CCA with ERSSTv3b & CFSv2 SSTs showed moderate & limited skill, resp. (GI 0.36) but very poor discrimination. Temperature will continue to be above normal. 5)Trinidad and Tobago:DJFA = 82% ; N = 14% ; B = 4% Note:CPT CCA with ERSSTv3b & CFSv2 SSTs showed good skill and discrimination. 6)Jamaica:DJFA = 57% ; N = 23% ; B = 20% Note:CPT CCA with ERSSTv3b & CFSv2 SSTs showed limited to fair skill and no to moderate discrimination. 7)Belize:DJFA = 63% ; N = 21% ; B = 16% Note: CPT CCA with ERSSTv3b showed moderate skill and moderate to fair discrimination. 8)St. Vincent:DJFA = 33% ; N = 39% ; B = 28% Note: CPT CCA with ERSSTv3b & CFSv2 SSTs showed fair skill and discrimination. 9)Dominica:DJFA = 25% ; N = 27% ; B = 48% Note: CPT CCA with limited to skill using ERSSTs & CFSv2 SSTs and no to fair discrimination.

Supporting probabilistic T 2m forecasts CARICOF national/sub-regional objective forecasts & outlook guidance: 10)Barbados:DJFA = 70% ; N = 26% ; B = 4% Note: CPT CCA with ERSSTs and CFSv2 SSTs showed good skill and discrimination. 11)Guyana:DJFA = % ; N = % ; B = % Note: 12)Grenada:DJFA = 42% ; N = 35% ; B = 23% MAMA = 27% ; N = 34% ; B = 39% Note: CPT CCA with ERSSTs and DJF CFSv2 SSTs showed very limited to fair skill and no to limited discrimination for DJF, good skill and moderate to fair discrimination for MAM. 13)Suriname: DJFA = % ; N = % ; B = % MAMA = % ; N = % ; B = % Note: CPT CCA with limited skill. IRI suggests 80% for AN for NDJ (but with longer climatology). 14)Aruba:DJFA = 76% ; N = 17% ; B = 7% Note: CPT CCA with ERSSTs and DJF CFSv2 SSTs showed very good skill and discrimination for DJF. 15)Antigua:DJFA = 36% ; N = 38% ; B = 26% Note: CPT CCA with ERSSTs and DJF CFSv2 SSTs showed limited to fair skill and no to moderate discrimination. 16)Bahamas:DJFA = 55% ; N = 20% ; B = 25% MAMA = 47% ; N = 21% ; B = 31% Note: CPT CCA with ERSSTs Oct (for DJF and MAM runs) and CFSv2 SSTs (DJF run) showed very limited skill and no to limited discrimination. 17)St. Kitts:DJFA = 73% ; N = 8% ; B = 19%.

Supporting probabilistic T 2m forecasts CARICOF national/sub-regional objective forecasts & outlook guidance: 10)Cuba West:DJFA = 28% ; N = 34% ; B = 44% (Tmax) DJFA = 75% ; N = 12% ; B = 13% (Tmin) Cuba Central:DJFA = 33% ; N = 25% ; B = 41% (Tmax) DJFA = 55% ; N = 20% ; B = 25% (Tmin) Cuba East:DJFA = 54% ; N = 17% ; B = 29% (Tmax) DJFA = 70% ; N = 20% ; B = 10% (Tmin) Note: CPT CCA with ERSSTs Oct and CFSv2 SSTs showed moderate to fair skill and no to fair discrimination.

CariCOF CPT output (background) and National/sub-regional T2m outlooks

Probabilistic DJF 2m temperature forecast DRAFT

Probabilistic MAM 2m temperature forecast DRAFT

Drought outlook

Supporting probabilistic SPI forecasts CARICOF national/sub-regional expert views: 1)Barbados:hydrol. year (SPI<-0.8)P = 43%Rel. Odds =3.2 (drought watch) Note: CPT CCA with moderate discrimination ROC )St. Maarten & NE Caribb: hydrol. year (SPI 3 (drought watch) Note: CPT CCA with moderate to good discrimination ROC )Trinidad & Tobago: hydrol. year (SPI<-0.8)P = 35%Rel. Odds =3.4 (drought watch) Note: CPT CCA with fair skill and moderate to good discrimination ROC )Jamaica: ASONDJFMA (SPI<-0.8)P = 52%Rel. Odds =7 (drought warning, with drought alert in SE portions of the country) Note: CPT CCA with limited skill and moderate to good discrimination ROC )Belize: hydrol. year (SPI<-0.8)P < 20%Rel. Odds <1 (no concern) Note: CPT CCA with negative skill and no to good discrimination ROC )St. Vincent:hydrol. year (SPI<-0.8)P = 63%Rel. Odds = 7 (drought warning) Note: CPT CCA with limited skill and good discrimination ROC )Grenada:hydrol. year (SPI<-0.8)P = 30%Rel. Odds = 1 (no concern) Note: CPT CCA with moderate skill. 8)Aruba: hydrol. year (SPI<-0.8)P = 33%Rel. Odds = 1.1 (no concern) Note: CPT CCA with fair skill and good discrimination. 9)St. Lucia:SONDJF (SPI < -1.3)P = 16%Rel. Odds = 2.3 Note: CPT CCA with very limited skill but very good discrimination.

Supporting probabilistic SPI forecasts CARICOF national/sub-regional expert views: 10)Cayman: hydrol. year (SPI<-0.8)P = 70%Rel. Odds =10.7 (drought alert) Note: CPT CCA with very good discrimination. 11) Dominica: hydrol. year (SPI<-0.8)P = 59%Rel. Odds =6 (drought warning) Note: CPT CCA with good discrimination. 12) Antigua: hydrol. year (SPI<-0.8)P = 46%Rel. Odds =3.7 (drought watch) Note: CPT CCA with negative skill but good discrimination. 13) Bahamas: hydrol. year (SPI<-0.8)P = 18%Rel. Odds =0.8 (no concern) Note: CPT CCA with moderate skill and very good discrimination. 14) Cuba: hydrol. year (SPI<-0.8) P(West) = 31% ; P(Central) = 33% ; P(East) = 49 Rel. Odds(West) =1.9 (no concern) ; Rel. Odds(Central) =2 (drought watch) ; Rel. Odds(West) =3.9 (drought watch) 15) St. Kitts: hydrol. year (SPI<-0.8)P = 61%Rel. Odds ~6 (drought warning)

SPI outlook Sep to Feb – areas under immediate drought concern? 103 November 2014’s update: Drought concerns have continued in the western Caribbean, in particular in the vicinity of Cayman Islands, Haïti and in Jamaica (where drought concerns have elevated since last update), as well as in portions of the Guianas. Greater concern since last update exists in Puerto Rico and parts of the eastern Caribbean. October 2014’s update

SPI outlook Hydrological Year – drought concern by the end of the Caribbean dry season (May 30 th, 2015)? 104 This 12-month SPI-based drought outlook uses observations until October 2014, with potential impacts on large surface water reserves and groundwater. Impactful hydrological drought is a concern in the Greater Antilles (except for Cuba), as well as in much of Leeward and Windward Islands, Trinidad & Tobago. Drought is possible in Belize, the ABC Islands, Barbados and the western Guianas.

SPI outlook Sep 2014 to May 2015 – shorter- / longer-term concern? 105 CONSERVE WATER!! Especially in Cayman, Haïti, Jamaica, and E Caribbean. Current drought situation: – Jamaica, Haïti and part of the Windward Islands are in drought and have suffered water shortages. Shorter-term: – We expect that the drought situation to possibly appear in some of the islands and improve over others. Longer-term: – It is possible that an El Niño will evolve by the end of this year. El Niño often results in a drier dry season (except for the NW Caribbean). – Water shortages may occur in portions of the Antilles during the dry season, which is our tourist season.

Interpreting the drought alert levels 106 ColourAlert levelMeaningSuggested action level GREEN No ConcernNo drought concern Business as usual YELLOW Drought WatchDrought possible Keep updated, conserve water ORANGE Drought Warning Drought evolving Be prepared, conserve water. protect RED Drought AlertDrought of immediate concern Take action, ration water, protect

Appendix

US Climate Prediction center – Climate Diagnostics bulletin

US Climate Prediction center – Climate Diagnostics bulletin

NOAA CPC NAO index monitoring/forecasting

Explanatory variables – IRI Predicted SSTs El Niño region Caribbean & tropical Atlantic

Explanatory variables – IRI Predicted SSTs El Niño region Caribbean & tropical Atlantic

Explanatory variables – ECMWF Predicted Tropical SSTs st!sea%20surface%20temperature!1%20month!Tropics!201401!ensemble%20mean!/

Explanatory variables – CPC/IRI ENSO Forecast

IRI – multi-model probabilistic rainfall forecast

EUROSIP – multi-model probabilistic rainfall forecast ummary!1%20month!Tropics!201310!/

ECMWF – ensemble probabilistic rainfall forecast

UK Met Office – probabilistic rainfall forecast ABOVE NORMAL BELOW

NOAA CPC – probabilistic rainfall forecast

APCC – multi-model probabilistic rainfall forecast

WMO LC for LRF-MME – Multi-model probabilistic rainfall forecast =4#

WMO LC for LRF-MME – Individual deterministic rainfall forecast

courtesy of Christophe Montout Météo France Arpège – probabilistic rainfall forecast ***

Japan Met Agency – probabilistic rainfall forecast

TRMM Monthly Rainfall Climatology January, February & March

TRMM Monthly Rainfall Climatology April, May & June

TRMM Monthly Rainfall Climatology July, August & September

TRMM Monthly Rainfall Climatology October, November & December

IRI – multi-model probabilistic T 2m forecast

EUROSIP – multi-model probabilistic T 2m forecast ummary!1%20month!Tropics!201309!/

ECMWF – ensemble probabilistic T 2m forecast

UK Met Office – probabilistic T 2m forecast ABOVE NORMAL BELOW

APCC – multi-model probabilistic T 2m forecast

WMO LC for LRF-MME – Multi-model probabilistic T 2m forecast =4#

WMO LC for LRF-MME – Individual deterministic T 2m forecast

WMO Lead Centre for Long-Range-Forecast – individual GPC models inter-model consistency

Japan Met Agency – probabilistic T2m forecast