Water Supply Forecast Listing

Header for Water Supply Period Rankings Page

Click here for Next Water Year's forecast (2027)

Summary for Water Year (2026)

Ensemble Date: 2026-08-15 Issued Date: 2026-08-15

#	ID	Servicing WFO	Forecast Period	Name	90% Exceedence KAF	50% Exceedence KAF	% Normal	10% Exceedence KAF	30 Year Normal
1	CONW1	SEW	APR-SEP	SKAGIT - NEAR CONCRETE	4003	4052	68	4199	5955
2	DRSW1	SEW	APR-SEP	DUNGENESS - NEAR SEQUIM	66.59	66.92	46	69.06	145
3	GREW4	RIW	APR-SEP	GREYS - AB RES NR ALPINE	230	230	62	231	371
4	JLKW4	RIW	APR-SEP	SNAKE - JACKSON LAKE AT DAM	628	629	74	633	849
5	SALW4	RIW	APR-SEP	SALT - ABV PALISADES RES NR ETNA	162	164	44	168	368
6	BONO3	PQR	APR-SEP	COLUMBIA - BONNEVILLE DAM	76055	76356	80	77053	95202
7	CASW1	PQR	APR-SEP	COWLITZ - AT CASTLE ROCK	1587	1602	64	1640	2504
8	ESTO3	PQR	APR-SEP	CLACKAMAS - AT ESTACADA	389	392	53	401	733
9	MEHO3	PQR	APR-SEP	NORTH SANTIAM - AT MEHAMA	428	431	50	446	855
10	MEWW1	PQR	APR-SEP	LEWIS - MERWIN DAM	605	611	56	637	1082
11	MYDW1	PQR	APR-SEP	COWLITZ - MAYFIELD RESERVOIR	1101	1113	60	1137	1864
12	SLMO3	PQR	APR-SEP	WILLAMETTE - AT SALEM	2581	2602	55	2693	4754
13	VIDO3	PQR	APR-SEP	MCKENZIE - NEAR VIDA	809	812	68	826	1195
14	WTLO3	PQR	APR-SEP	SOUTH SANTIAM - AT WATERLOO	295	296	50	310	590
15	AMFI1	PIH	APR-SEP	SNAKE - AT AMERICAN FALLS DAM	710	730	28	760	2624
16	ANTI1	PIH	APR-SEP	HENRYS FORK - AT ST. ANTHONY	389	398	50	410	794
17	CHEI1	PIH	APR-SEP	FALL RIVER - NEAR CHESTER	189	191	51	195	377
18	HALI1	PIH	APR-SEP	BIG WOOD - AT HAILEY	176	176	69	177	257
19	HEII1	PIH	APR-SEP	SNAKE - NEAR HEISE	2726	2733	71	2751	3849
20	HWRI1	PIH	APR-SEP	BIG LOST - AT HOWELL RANCH NEAR CHILLY	142	142	83	142	172
21	MACI1	PIH	APR-SEP	BIG LOST - MACKAY RESERVOIR NEAR MACKAY	98.8	99.14	73	99.82	136
22	MAGI1	PIH	APR-SEP	BIG WOOD - MAGIC DAM	92.32	92.72	39	94.68	240
23	PALI1	PIH	APR-SEP	SNAKE - NEAR IRWIN	2601	2608	73	2626	3577
24	REXI1	PIH	APR-SEP	HENRYS FORK - AT REXBURG	842	851	50	863	1710
25	RIRI1	PIH	APR-SEP	WILLOW CREEK - NEAR RIRIE	6.28	6.38	11	6.68	60.33
26	SFLN2	PIH	APR-SEP	SALMON FALLS CREEK - NR SAN JACINTO	10.16	10.37	15	10.88	67.85
27	SHYI1	PIH	APR-SEP	SNAKE - NEAR SHELLEY	3068	3089	63	3117	4905
28	TEAI1	PIH	APR-SEP	TETON - NEAR ST. ANTHONY	278	280	63	283	447
29	TOPI1	PIH	APR-SEP	PORTNEUF - AT TOPAZ	42.21	42.76	59	43.48	72.20
30	WODI1	PIH	APR-SEP	LITTLE WOOD - NEAR CAREY	38.81	39.05	51	39.75	76.59
31	BUMW1	PDT	APR-SEP	BUMPING - BELOW BUMPING DAM	70.51	70.61	56	70.95	125
32	CLEW1	PDT	APR-SEP	CLE ELUM - NEAR ROSLYN	182	183	44	189	419
33	GIBO3	PDT	APR-SEP	UMATILLA - NEAR GIBBON	53.92	53.97	65	54.09	82.43
34	HCDI1	PDT	APR-SEP	SNAKE - AT HELLS CANYON DAM	4311	4329	64	4452	6725
35	HLKW1	PDT	APR-SEP	YAKIMA - NEAR HORLICK	487	488	51	498	962
36	IMNO3	PDT	APR-SEP	IMNAHA - AT IMNAHA	133	133	48	133	277
37	JDAO3	PDT	APR-SEP	COLUMBIA - JOHN DAY DAM	76910	77208	84	77898	92354
38	KACW1	PDT	APR-SEP	KACHESS - NEAR EASTON	50.93	51.13	45	52.73	114
39	KEEW1	PDT	APR-SEP	YAKIMA - NEAR MARTIN	78.66	79.18	61	83.79	129
40	KIOW1	PDT	APR-SEP	YAKIMA - AT KIONA	670	673	59	683	1149
41	LGNO3	PDT	APR-SEP	GRANDE RONDE - NEAR PERRY	51.14	51.32	29	51.76	176
42	LSTO3	PDT	APR-SEP	LOSTINE - NR LOSTINE	66.79	66.97	58	68.57	116
43	MCDW1	PDT	APR-SEP	COLUMBIA - MCNARY DAM	75221	75520	81	76206	92790
44	MODO3	PDT	APR-SEP	DESCHUTES - AT MOODY NR BIGGS	1436	1437	76	1437	1902
45	MONO3	PDT	APR-SEP	NF JOHN DAY - AT MONUMENT	210	210	37	211	564
46	NACW1	PDT	APR-SEP	NACHES - NEAR NACHES	489	492	61	495	807
47	PARW1	PDT	APR-SEP	YAKIMA - NEAR PARKER	968	973	51	985	1899
48	PDTO3	PDT	APR-SEP	UMATILLA - AT PENDLETON	105	105	66	105	158
49	RIMW1	PDT	APR-SEP	TIETON - AT TIETON DAM	141	143	64	146	225
50	SERO3	PDT	APR-SEP	JOHN DAY - AT SERVICE CK	274	275	34	277	798
51	TDAO3	PDT	APR-SEP	COLUMBIA - THE DALLES DAM	77272	77571	82	78262	94166
52	TRYO3	PDT	APR-SEP	GRANDE RONDE - TROY	649	650	49	652	1331
53	UNYO3	PDT	APR-SEP	BURNT - Unity Dam & Burnt RVR NR Hereford	3.99	4.05	13	4.43	31.00
54	ALFW1	OTX	APR-SEP	PEND OREILLE - ALBENI FALLS DAM	11345	11369	85	11445	13347
55	ARDQ2	OTX	APR-SEP	COLUMBIA - ARROW LAKES (HUGH KEENLEYSIDE DAM)	23977	24275	101	24586	24059
56	BFEI1	OTX	APR-SEP	KOOTENAI - AT BONNERS FERRY	8274	8306	98	8413	8463
57	CABI1	OTX	APR-SEP	CLARK FORK - CABINET GORGE DAM	10309	10323	89	10353	11639
58	CHDW1	OTX	APR-SEP	CHELAN - LAKE CHELAN DAM	836	837	73	842	1139
59	CIBW1	OTX	APR-SEP	COLUMBIA - AT INTL BOUNDARY	53331	53626	94	54174	56951
60	CLDI1	OTX	APR-SEP	ST JOE - AT CALDER	789	790	69	791	1138
61	COEI1	OTX	APR-SEP	COEUR D ALENE - COEUR D ALENE LAKE	1376	1377	55	1378	2504
62	EASI1	OTX	APR-SEP	MOYIE - AT EASTPORT	310	310	78	311	395
63	ENVI1	OTX	APR-SEP	NF COEUR D ALENE - AT ENAVILLE	373	373	50	374	743
64	GCDW1	OTX	APR-SEP	COLUMBIA - GRAND COULEE DAM	55481	55776	91	56349	61483
65	LAUW1	OTX	APR-SEP	KETTLE - AT LAURIER	1027	1031	53	1047	1954
66	LEOI1	OTX	APR-SEP	KOOTENAI - AT LEONIA	7662	7693	99	7800	7803
67	LGDW1	OTX	APR-SEP	SNAKE - LOWER GRANITE DAM	15559	15592	70	15737	22232
68	LLKW1	OTX	APR-SEP	SPOKANE - AT LONGLAKE	1677	1678	58	1680	2901
69	NITW1	OTX	APR-SEP	SIMILKAMEEN - NEAR NIGHTHAWK	982	987	72	993	1366
70	PATW1	OTX	APR-SEP	METHOW - NEAR PATEROS	827	827	86	828	965
71	PESW1	OTX	APR-SEP	WENATCHEE - AT PESHASTIN	972	972	65	973	1496
72	PRDW1	OTX	APR-SEP	COLUMBIA - BLO PRIEST RAPIDS DAM	60282	60573	89	61167	68162
73	PRTI1	OTX	APR-SEP	PRIEST - NEAR PRIEST RIVER	426	430	51	435	843
74	RISW1	OTX	APR-SEP	COLUMBIA - BLO ROCK ISLAND DAM	59488	59779	89	60372	67524
75	SPDI1	OTX	APR-SEP	CLEARWATER - AT SPALDING	5488	5498	73	5513	7481
76	SPOW1	OTX	APR-SEP	SPOKANE - AT SPOKANE	1465	1466	57	1467	2587
77	STHW1	OTX	APR-SEP	STEHEKIN - AT STEHEKIN	593	594	73	598	814
78	TONW1	OTX	APR-SEP	OKANOGAN - NEAR TONASKET	1047	1052	61	1068	1720
79	ABBM8	MSO	APR-SEP	CLARK FORK - ABOVE BLACKFOOT	522	528	78	535	680
80	ABOM8	MSO	APR-SEP	CLARK FORK - ABOVE MISSOULA	1411	1417	90	1425	1571
81	BELM8	MSO	APR-SEP	CLARK FORK - BELOW MISSOULA	2551	2560	89	2573	2893
82	BITM8	MSO	APR-SEP	BITTERROOT - NEAR MISSOULA	1193	1195	93	1201	1289
83	BONM8	MSO	APR-SEP	BLACKFOOT - NEAR BONNER	889	889	100	890	891
84	CFMM8	MSO	APR-SEP	FLATHEAD - AT COLUMBIA FALLS	5255	5255	93	5264	5634
85	DARM8	MSO	APR-SEP	BITTERROOT - NEAR DARBY	472	473	91	477	519
86	DWRI1	MSO	APR-SEP	NF CLEARWATER - DWORSHAK DAM	1928	1932	74	1936	2620
87	FCFM8	MSO	APR-SEP	NF FLATHEAD - NEAR COLUMBIA FALLS	1686	1686	96	1688	1750
88	HHWM8	MSO	APR-SEP	SF FLATHEAD - HUNGRY HORSE DAM	1939	1939	93	1944	2088
89	KERM8	MSO	APR-SEP	FLATHEAD - SELI’Š KSANKA QLISPE’ DAM	6106	6109	93	6121	6577
90	LYDM8	MSO	APR-SEP	KOOTENAI - LIBBY DAM	6745	6775	105	6875	6429
91	ORFI1	MSO	APR-SEP	CLEARWATER - AT OROFINO	3482	3487	75	3497	4632
92	PLNM8	MSO	APR-SEP	CLARK FORK - NEAR PLAINS	9874	9887	93	9913	10574
93	SMNI1	MSO	APR-SEP	SALMON - AT SALMON	736	740	80	745	929
94	SRGM8	MSO	APR-SEP	CLARK FORK - AT ST REGIS	3350	3360	89	3372	3771
95	WGCM8	MSO	APR-SEP	MF FLATHEAD - NEAR WEST GLACIER	1661	1661	98	1664	1697
96	WHBI1	MSO	APR-SEP	SALMON - AT WHITEBIRD	4843	4847	79	4854	6158
97	RYGO3	MFR	APR-SEP	ROGUE - AT RAYGOLD	445	447	54	454	831
98	WDHN2	LKN	APR-SEP	OWYHEE - WILDHORSE DAM	-4	-3.9	-24	-3.66	15.92
99	BIRQ2	CAN	APR-SEP	COLUMBIA - AT BIRCHBANK	41333	41633	98	42152	42578
100	DCDQ2	CAN	APR-SEP	DUNCAN - DUNCAN DAM	2325	2352	106	2380	2224
101	MCDQ2	CAN	APR-SEP	COLUMBIA - MICA DAM	12711	12951	105	13127	12296
102	QBYQ2	CAN	APR-SEP	KOOTENAI - KOOTENAY L AT QUEENS BAY	15156	15192	96	15333	15842
103	REVQ2	CAN	APR-SEP	COLUMBIA - REVELSTOKE DAM	17758	18013	104	18279	17242
104	SLCQ2	CAN	APR-SEP	SLOCAN - NEAR CRESCENT VALLEY	1743	1748	90	1790	1933
105	SMKQ2	CAN	APR-SEP	SIMILKAMEEN - NEAR HEDLEY	696	700	70	707	1004
106	ARAI1	BOI	APR-SEP	SF BOISE - ANDERSON RANCH DAM	309	310	63	312	495
107	BEUO3	BOI	APR-SEP	NF MALHEUR - AT BEULAH	16.69	16.69	28	16.69	59.29
108	BRNI1	BOI	APR-SEP	SNAKE - BROWNLEE DAM	4204	4222	66	4346	6398
109	BUSO3	BOI	APR-SEP	SILVIES - NEAR BURNS	14.39	14.51	20	14.81	71.47
110	CSCI1	BOI	APR-SEP	NF PAYETTE - CASCADE DAM	331	334	69	341	487
111	DONO3	BOI	APR-SEP	DONNER UND BLITZEN - NR FRENCHGLEN	25.68	25.72	41	25.97	62.51
112	DRBI1	BOI	APR-SEP	DEADWOOD - BELOW DEADWOOD RES	102	102	76	103	135
113	EGCO3	BOI	APR-SEP	EAGLE CREEK - ABOVE SKULL CK	93.65	93.66	54	93.71	174
114	EMMI1	BOI	APR-SEP	PAYETTE - NEAR EMMETT	1187	1189	90	1194	1325
115	HOTI1	BOI	APR-SEP	BRUNEAU - NEAR HOT SPRINGS	32.66	33.04	18	34.02	183
116	HRSI1	BOI	APR-SEP	PAYETTE - NEAR HORSESHOE BEND	1192	1196	75	1208	1597
117	LUCI1	BOI	APR-SEP	BOISE - LUCKY PEAK DAM	811	813	61	818	1329
118	MADO3	BOI	APR-SEP	MALHEUR - NEAR DREWSEY	12.62	12.63	19	12.86	64.84
119	OWYO3	BOI	APR-SEP	OWYHEE - OWYHEE DAM	75.19	76.48	23	79.52	336
120	PARI1	BOI	APR-SEP	BOISE - NEAR PARMA	406	408	70	410	584
121	SKHI1	BOI	APR-SEP	SNAKE - AT KING HILL	2358	2374	70	2488	3412
122	SWAI1	BOI	APR-SEP	SNAKE - BELOW SWAN FALLS	1988	2002	61	2104	3258
123	WEII1	BOI	APR-SEP	SNAKE - AT WEISER	4033	4051	68	4175	5956
124	WSRI1	BOI	APR-SEP	WEISER - NEAR WEISER	268	268	69	269	389

Link to main Northwest River Forecast Center (NWRFC) web site

6388