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Water Year
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LEWIS - MERWIN DAM
(
MEWW1
)
Forecasts for Water Year
2026
Official Water Supply
ESP with 10 Days QPF
Ensemble:
2026-08-15
Issued:
2026-08-15
Hide Forecast
Forecast
Period
Forecasts Are in KAF
30 Year
Average
(1991-2020)
90 %
50 %
%
Average
10 %
APR-SEP
605
611
56
637
1082
APR-JUL
532
532
60
532
881
APR-AUG
573
573
59
574
969
JAN-SEP
1835
1841
78
1867
2363
JAN-JUL
1762
1762
82
1762
2162
OCT-SEP
3120
3126
91
3152
3417
Experimental Water Supply
HEFS with 15 days EQPF
Ensemble:
2026-08-15
Issued:
2026-08-15
Hide Forecast
APR-SEP
605
610
56
635
1082
APR-JUL
532
532
60
532
881
APR-AUG
573
573
59
573
969
JAN-SEP
1835
1840
78
1865
2363
JAN-JUL
1762
1762
82
1762
2162
OCT-SEP
3120
3125
91
3150
3417
Reference
ESP with 0 Days QPF
Ensemble:
2026-08-15
Issued:
2026-08-15
Hide Forecast
APR-SEP
605
611
56
637
1082
APR-JUL
532
532
60
532
881
APR-AUG
573
573
59
577
969
JAN-SEP
1835
1841
78
1867
2363
JAN-JUL
1762
1762
82
1762
2162
OCT-SEP
3120
3126
91
3152
3417
Move the mouse over the desired "Forecast Period" to display a graph.
ESP10, 225, 274, 319, 368, 443, 70, , 74
ESP10, 225, 274, 319, 368, 442, 72, , 76
ESP10, 225, 274, 319, 368, 442, 74, , 78
ESP10, 225, 274, 319, 368, 442, 76, , 80
ESP10, 225, 274, 319, 368, 442, 78, , 82
ESP10, 225, 274, 319, 368, 443, 81, , 85
ESP10, 224, 273, 319, 368, 443, 83, , 87
ESP10, 224, 274, 319, 368, 443, 85, , 89
ESP10, 225, 274, 319, 368, 443, 87, , 91
ESP10, 224, 273, 319, 368, 442, 89, , 93
ESP10, 225, 273, 319, 368, 443, 91, , 95
ESP10, 225, 273, 319, 368, 443, 93, , 97
ESP10, 225, 273, 319, 368, 444, 95, , 99
ESP10, 224, 273, 319, 368, 444, 97, , 101
ESP10, 224, 273, 319, 368, 445, 99, , 103
ESP10, 224, 273, 319, 368, 444, 102, , 106
ESP10, 224, 272, 319, 368, 443, 104, , 108
ESP10, 224, 273, 319, 368, 444, 106, , 110
ESP10, 224, 272, 318, 367, 443, 108, , 112
ESP10, 224, 273, 319, 369, 444, 110, , 114
ESP10, 224, 272, 318, 368, 443, 112, , 116
ESP10, 224, 274, 319, 370, 445, 114, , 118
ESP10, 224, 273, 318, 369, 445, 116, , 120
ESP10, 224, 273, 318, 370, 445, 118, , 122
ESP10, 225, 274, 319, 370, 446, 120, , 124
ESP10, 226, 274, 318, 370, 446, 122, , 126
ESP10, 227, 275, 319, 370, 447, 125, , 129
ESP10, 228, 275, 319, 371, 447, 127, , 131
ESP10, 228, 275, 318, 370, 447, 129, , 133
ESP10, 228, 275, 318, 371, 446, 131, , 135
ESP10, 228, 274, 318, 372, 446, 133, , 137
ESP10, 229, 275, 318, 374, 447, 135, , 139
ESP10, 229, 275, 318, 374, 447, 137, , 141
ESP10, 231, 275, 319, 374, 447, 139, , 143
ESP10, 231, 275, 318, 376, 447, 141, , 145
ESP10, 232, 275, 319, 377, 448, 143, , 147
ESP10, 232, 276, 319, 379, 450, 145, , 149
ESP10, 230, 274, 318, 377, 450, 148, , 152
ESP10, 230, 274, 317, 376, 450, 150, , 154
ESP10, 231, 276, 316, 377, 451, 152, , 156
ESP10, 231, 276, 318, 377, 452, 154, , 158
ESP10, 232, 278, 319, 378, 452, 156, , 160
ESP10, 230, 278, 319, 376, 450, 158, , 162
ESP10, 235, 284, 324, 381, 455, 160, , 164
ESP10, 234, 288, 326, 383, 455, 162, , 166
ESP10, 233, 287, 324, 381, 453, 164, , 168
ESP10, 235, 289, 327, 385, 455, 166, , 170
ESP10, 234, 290, 329, 386, 455, 169, , 173
ESP10, 232, 288, 327, 385, 453, 171, , 175
ESP10, 234, 290, 328, 388, 454, 173, , 177
ESP10, 234, 292, 329, 391, 455, 175, , 179
ESP10, 233, 293, 328, 391, 454, 177, , 181
ESP10, 232, 294, 329, 391, 454, 179, , 183
ESP10, 235, 296, 332, 393, 456, 181, , 185
ESP10, 234, 296, 331, 392, 455, 183, , 187
ESP10, 236, 298, 332, 393, 457, 185, , 189
ESP10, 236, 299, 331, 393, 457, 187, , 191
ESP10, 237, 304, 332, 393, 457, 189, , 193
ESP10, 239, 304, 332, 393, 457, 192, , 196
ESP10, 239, 302, 331, 392, 456, 194, , 198
ESP10, 244, 306, 334, 394, 459, 196, , 200
ESP10, 244, 306, 336, 395, 460, 198, , 202
ESP10, 245, 307, 338, 395, 460, 200, , 204
ESP10, 244, 305, 338, 394, 459, 202, , 206
ESP10, 247, 307, 341, 396, 461, 204, , 208
ESP10, 249, 307, 343, 397, 462, 206, , 210
ESP10, 249, 308, 344, 397, 463, 208, , 212
ESP10, 250, 309, 344, 397, 464, 210, , 214
ESP10, 251, 309, 344, 397, 465, 212, , 216
ESP10, 252, 309, 344, 397, 464, 215, , 219
ESP10, 242, 297, 334, 388, 454, 217, , 221
ESP10, 239, 295, 331, 386, 451, 219, , 223
ESP10, 238, 293, 331, 386, 450, 221, , 225
ESP10, 242, 296, 335, 391, 452, 223, , 227
ESP10, 244, 296, 336, 392, 453, 225, , 229
ESP10, 245, 296, 337, 392, 454, 227, , 231
ESP10, 243, 293, 338, 389, 452, 229, , 233
ESP10, 245, 292, 338, 390, 451, 231, , 235
ESP10, 244, 291, 340, 389, 450, 233, , 237
ESP10, 242, 288, 338, 390, 447, 236, , 240
ESP10, 249, 294, 345, 396, 455, 238, , 242
ESP10, 248, 293, 347, 396, 455, 240, , 244
ESP10, 251, 298, 352, 400, 460, 242, , 246
ESP10, 254, 298, 352, 401, 461, 244, , 248
ESP10, 252, 295, 349, 399, 460, 246, , 250
ESP10, 250, 291, 346, 396, 458, 248, , 252
ESP10, 251, 291, 345, 395, 458, 250, , 254
ESP10, 253, 294, 348, 399, 460, 252, , 256
ESP10, 253, 294, 348, 399, 460, 254, , 258
ESP10, 253, 296, 351, 401, 460, 256, , 260
ESP10, 254, 301, 356, 404, 462, 259, , 263
ESP10, 252, 301, 355, 403, 460, 261, , 265
ESP10, 250, 299, 352, 400, 458, 263, , 267
ESP10, 250, 301, 353, 401, 457, 265, , 269
ESP10, 248, 300, 352, 400, 455, 267, , 271
ESP10, 248, 299, 351, 399, 454, 269, , 273
ESP10, 247, 299, 352, 399, 452, 271, , 275
ESP10, 252, 303, 356, 404, 456, 273, , 277
ESP10, 254, 305, 357, 405, 456, 275, , 279
ESP10, 254, 305, 356, 405, 455, 277, , 281
ESP10, 256, 305, 356, 407, 454, 279, , 283
ESP10, 257, 305, 356, 407, 455, 282, , 286
ESP10, 258, 307, 357, 407, 455, 284, , 288
ESP10, 259, 306, 360, 407, 455, 286, , 290
ESP10, 263, 306, 364, 409, 457, 288, , 292
ESP10, 264, 306, 369, 408, 457, 290, , 294
ESP10, 262, 304, 368, 406, 455, 292, , 296
ESP10, 263, 306, 373, 408, 460, 294, , 298
ESP10, 264, 307, 376, 410, 462, 296, , 300
ESP10, 267, 310, 381, 413, 465, 298, , 302
ESP10, 267, 310, 381, 413, 464, 300, , 304
ESP10, 267, 310, 381, 414, 465, 303, , 307
ESP10, 269, 312, 383, 417, 465, 305, , 309
ESP10, 269, 312, 383, 418, 466, 307, , 311
ESP10, 269, 312, 383, 420, 466, 309, , 313
ESP10, 270, 313, 384, 421, 467, 311, , 315
ESP10, 272, 316, 389, 425, 469, 313, , 317
ESP10, 269, 314, 387, 422, 467, 315, , 319
ESP10, 269, 314, 388, 422, 468, 317, , 321
ESP10, 270, 315, 388, 423, 469, 319, , 323
ESP10, 267, 314, 386, 419, 466, 321, , 325
ESP10, 269, 316, 388, 423, 467, 323, , 327
ESP10, 265, 313, 384, 417, 461, 326, , 330
ESP10, 266, 315, 383, 416, 461, 328, , 332
ESP10, 267, 316, 383, 423, 466, 330, , 334
ESP10, 267, 316, 382, 424, 465, 332, , 336
ESP10, 266, 314, 380, 422, 465, 334, , 338
ESP10, 268, 317, 383, 427, 467, 336, , 340
ESP10, 265, 316, 379, 425, 464, 338, , 342
ESP10, 264, 317, 381, 424, 465, 340, , 344
ESP10, 264, 316, 380, 424, 466, 342, , 346
ESP10, 265, 315, 378, 422, 467, 344, , 348
ESP10, 258, 306, 374, 417, 463, 346, , 350
ESP10, 255, 304, 375, 417, 464, 349, , 353
ESP10, 254, 304, 374, 417, 464, 351, , 355
ESP10, 246, 295, 367, 408, 457, 353, , 357
ESP10, 250, 301, 370, 410, 459, 355, , 359
ESP10, 254, 306, 373, 415, 463, 357, , 361
ESP10, 247, 296, 365, 406, 454, 359, , 363
ESP10, 270, 304, 372, 416, 461, 361, , 365
ESP10, 273, 305, 371, 418, 458, 363, , 367
ESP10, 284, 309, 374, 422, 461, 365, , 369
ESP10, 285, 310, 375, 422, 463, 367, , 371
ESP10, 287, 313, 377, 423, 464, 370, , 374
ESP10, 291, 317, 381, 426, 468, 372, , 376
ESP10, 292, 318, 386, 426, 468, 374, , 378
ESP10, 290, 316, 384, 426, 465, 376, , 380
ESP10, 287, 313, 381, 424, 461, 378, , 382
ESP10, 285, 314, 385, 427, 461, 380, , 384
ESP10, 283, 313, 386, 429, 460, 382, , 386
ESP10, 284, 314, 387, 433, 461, 384, , 388
ESP10, 283, 318, 385, 432, 458, 386, , 390
ESP10, 282, 315, 383, 430, 455, 388, , 392
ESP10, 275, 308, 376, 423, 448, 390, , 394
ESP10, 270, 304, 371, 417, 443, 393, , 397
ESP10, 267, 303, 370, 414, 440, 395, , 399
ESP10, 267, 303, 370, 415, 442, 397, , 401
ESP10, 263, 299, 370, 411, 440, 399, , 403
ESP10, 264, 300, 374, 413, 442, 401, , 405
ESP10, 268, 307, 380, 419, 447, 403, , 407
ESP10, 264, 305, 374, 413, 443, 405, , 409
ESP10, 265, 304, 372, 411, 442, 407, , 411
ESP10, 278, 315, 382, 425, 454, 409, , 413
ESP10, 278, 315, 379, 424, 456, 411, , 415
ESP10, 280, 319, 379, 425, 457, 413, , 417
ESP10, 272, 313, 375, 418, 451, 416, , 420
ESP10, 264, 310, 369, 413, 445, 418, , 422
ESP10, 271, 323, 387, 423, 455, 420, , 424
ESP10, 281, 338, 390, 427, 463, 422, , 426
ESP10, 291, 351, 400, 432, 464, 424, , 428
ESP10, 296, 351, 400, 431, 465, 426, , 430
ESP10, 295, 354, 402, 434, 469, 428, , 432
ESP10, 297, 354, 402, 433, 467, 430, , 434
ESP10, 294, 347, 392, 427, 458, 432, , 436
ESP10, 294, 345, 389, 423, 458, 434, , 438
ESP10, 308, 363, 396, 430, 467, 437, , 441
ESP10, 306, 359, 393, 424, 456, 439, , 443
ESP10, 318, 367, 403, 433, 467, 441, , 445
ESP10, 327, 368, 409, 443, 473, 443, , 447
ESP10, 332, 369, 411, 446, 476, 445, , 449
ESP10, 341, 373, 417, 452, 479, 447, , 451
ESP10, 346, 381, 423, 457, 485, 449, , 453
ESP10, 346, 386, 426, 461, 489, 451, , 455
ESP10, 345, 385, 434, 464, 489, 453, , 457
ESP10, 345, 383, 432, 469, 495, 455, , 459
ESP10, 351, 384, 434, 472, 498, 457, , 461
ESP10, 348, 381, 430, 469, 495, 460, , 464
ESP10, 357, 385, 442, 474, 503, 462, , 466
ESP10, 348, 377, 431, 464, 493, 464, , 468
ESP10, 345, 368, 422, 455, 485, 466, , 470
ESP10, 345, 380, 424, 455, 482, 468, , 472
ESP10, 341, 372, 415, 449, 474, 470, , 474
ESP10, 339, 368, 410, 444, 468, 472, , 476
ESP10, 350, 381, 413, 448, 472, 474, , 478
ESP10, 352, 389, 415, 455, 474, 476, , 480
ESP10, 359, 396, 426, 461, 482, 478, , 482
ESP10, 361, 403, 432, 463, 481, 480, , 484
ESP10, 363, 409, 437, 469, 483, 483, , 487
ESP10, 366, 413, 448, 472, 486, 485, , 489
ESP10, 369, 418, 448, 472, 486, 487, , 491
ESP10, 375, 424, 450, 473, 488, 489, , 493
ESP10, 379, 425, 452, 474, 488, 491, , 495
ESP10, 383, 425, 450, 473, 485, 493, , 497
ESP10, 388, 424, 453, 471, 483, 495, , 499
ESP10, 393, 429, 457, 473, 486, 497, , 501
ESP10, 395, 434, 459, 476, 489, 499, , 503
ESP10, 399, 434, 461, 478, 489, 501, , 505
ESP10, 404, 436, 465, 481, 490, 504, , 508
ESP10, 404, 438, 467, 482, 490, 506, , 510
ESP10, 404, 440, 467, 482, 490, 508, , 512
ESP10, 404, 441, 466, 483, 490, 510, , 514
ESP10, 406, 444, 467, 485, 491, 512, , 516
ESP10, 408, 445, 467, 485, 491, 514, , 518
ESP10, 413, 449, 467, 485, 492, 516, , 520
ESP10, 416, 451, 467, 485, 493, 518, , 522
ESP10, 421, 456, 474, 487, 493, 520, , 524
ESP10, 423, 455, 473, 487, 492, 522, , 526
ESP10, 427, 457, 478, 488, 492, 524, , 528
ESP10, 425, 454, 476, 487, 492, 527, , 531
ESP10, 430, 455, 479, 488, 493, 529, , 533
ESP10, 438, 466, 487, 496, 501, 531, , 535
ESP10, 435, 463, 485, 493, 498, 533, , 537
ESP10, 435, 464, 484, 493, 497, 535, , 539
ESP10, 433, 464, 483, 492, 496, 537, , 541
ESP10, 425, 457, 476, 487, 491, 539, , 543
ESP10, 424, 455, 476, 486, 490, 541, , 545
ESP10, 422, 454, 475, 484, 488, 543, , 547
ESP10, 418, 450, 469, 480, 484, 545, , 549
ESP10, 419, 454, 473, 481, 485, 547, , 551
ESP10, 420, 457, 474, 481, 485, 550, , 554
ESP10, 413, 451, 469, 478, 482, 552, , 556
ESP10, 422, 454, 473, 480, 484, 554, , 558
ESP10, 420, 453, 472, 478, 482, 556, , 560
ESP10, 427, 456, 474, 480, 483, 558, , 562
ESP10, 432, 461, 475, 482, 485, 560, , 564
ESP10, 439, 465, 476, 484, 485, 562, , 566
ESP10, 436, 464, 475, 483, 485, 564, , 568
ESP10, 432, 461, 473, 480, 481, 566, , 570
ESP10, 445, 470, 478, 483, 485, 568, , 572
ESP10, 447, 470, 478, 483, 484, 571, , 575
ESP10, 451, 470, 477, 482, 484, 573, , 577
ESP10, 455, 470, 477, 482, 484, 575, , 579
ESP10, 456, 471, 478, 482, 484, 577, , 581
ESP10, 459, 471, 479, 483, 484, 579, , 583
ESP10, 459, 472, 480, 483, 485, 581, , 585
ESP10, 459, 470, 477, 481, 482, 583, , 587
ESP10, 461, 471, 477, 481, 483, 585, , 589
ESP10, 460, 470, 476, 480, 481, 587, , 591
ESP10, 456, 467, 471, 475, 476, 589, , 593
ESP10, 454, 465, 469, 472, 474, 591, , 595
ESP10, 456, 467, 471, 474, 476, 594, , 598
ESP10, 455, 466, 470, 473, 474, 596, , 600
ESP10, 457, 468, 472, 474, 476, 598, , 602
ESP10, 459, 468, 473, 475, 476, 600, , 604
ESP10, 460, 468, 473, 475, 476, 602, , 606
ESP10, 460, 469, 473, 475, 476, 604, , 608
ESP10, 460, 469, 473, 475, 476, 606, , 610
ESP10, 460, 469, 474, 475, 477, 608, , 612
ESP10, 461, 470, 474, 475, 477, 610, , 614
ESP10, 461, 470, 474, 475, 476, 612, , 616
ESP10, 461, 471, 474, 476, 476, 614, , 618
ESP10, 461, 470, 474, 476, 476, 617, , 621
ESP10, 461, 470, 474, 476, 476, 619, , 623
ESP10, 462, 469, 473, 475, 476, 621, , 625
ESP10, 463, 470, 473, 475, 476, 623, , 627
ESP10, 462, 469, 473, 475, 476, 625, , 629
ESP10, 463, 470, 473, 475, 476, 627, , 631
ESP10, 463, 470, 473, 475, 476, 629, , 633
ESP10, 462, 470, 473, 475, 476, 631, , 635
ESP10, 462, 470, 473, 475, 475, 633, , 637
ESP10, 462, 469, 472, 474, 475, 635, , 639
ESP10, 462, 469, 472, 474, 475, 638, , 642
ESP10, 462, 469, 472, 474, 475, 640, , 644
ESP10, 462, 469, 472, 474, 475, 642, , 646
ESP10, 462, 469, 472, 474, 475, 644, , 648
ESP10, 460, 467, 470, 472, 473, 646, , 650
ESP10, 460, 467, 470, 472, 473, 648, , 652
ESP10, 460, 467, 470, 472, 473, 650, , 654
ESP10, 460, 467, 470, 472, 473, 652, , 656
ESP10, 459, 467, 470, 472, 473, 654, , 658
ESP10, 460, 467, 470, 472, 473, 656, , 660
ESP10, 460, 467, 470, 472, 473, 658, , 662
ESP10, 459, 467, 470, 472, 473, 661, , 665
ESP10, 459, 467, 470, 472, 473, 663, , 667
ESP10, 459, 467, 470, 472, 473, 665, , 669
ESP10, 459, 467, 470, 472, 473, 667, , 671
ESP10, 459, 467, 470, 472, 472, 669, , 673
ESP10, 459, 467, 470, 472, 472, 671, , 675
ESP10, 459, 466, 470, 472, 472, 673, , 677
ESP10, 459, 467, 470, 472, 472, 675, , 679
ESP10, 459, 466, 470, 472, 472, 677, , 681
ESP10, 459, 466, 469, 471, 472, 679, , 683
ESP10, 460, 467, 470, 472, 472, 681, , 685
ESP10, 460, 466, 469, 471, 472, 684, , 688
ESP10, 460, 466, 469, 471, 472, 686, , 690
ESP10, 460, 467, 470, 472, 472, 688, , 692
ESP10, 460, 467, 470, 472, 473, 690, , 694
ESP10, 461, 467, 470, 472, 473, 692, , 696
ESP10, 461, 467, 471, 473, 473, 694, , 698
ESP10, 461, 467, 471, 473, 473, 696, , 700
ESP10, 462, 467, 470, 472, 473, 698, , 702
ESP10, 462, 467, 471, 473, 473, 700, , 704
ESP10, 462, 467, 470, 472, 473, 702, , 706
ESP10, 462, 468, 471, 473, 473, 705, , 709
ESP10, 462, 467, 471, 472, 473, 707, , 711
ESP10, 462, 467, 471, 472, 473, 709, , 713
ESP10, 462, 467, 471, 473, 473, 711, , 715
ESP10, 462, 467, 471, 472, 473, 713, , 717
ESP10, 462, 467, 471, 472, 473, 715, , 719
ESP10, 462, 467, 471, 473, 473, 717, , 721
ESP10, 462, 467, 471, 473, 473, 719, , 723
ESP10, 462, 467, 471, 472, 473, 721, , 725
ESP10, 462, 467, 471, 472, 473, 723, , 727
ESP10, 462, 467, 471, 473, 473, 725, , 729
ESP10, 462, 467, 471, 473, 473, 728, , 732
ESP10, 462, 467, 471, 473, 473, 730, , 734
ESP10, 462, 467, 471, 473, 473, 732, , 736
ESP10, 462, 467, 471, 473, 473, 734, , 738
Max Scale
Scale To Data
Scale To Last 45 Days
Show Min/Max Ensemble Volume
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ESP10
HEFS
ESP0
Data Files
/chpsesp/ensemble/watersupply/MEWW1W_SQIN.ESPF10.csv
MEWW1W_SQIN.ESPF0.csv|2026-08-15
MEWW1W_SQIN.ESPF10.csv|2026-08-15
MEWW1W_SQIN.ESPFM.csv|2026-08-15
APR-SEP
LEWIS - MERWIN DAM
(
MEWW1
)
Forecasts for Water Year
2027
Official Water Supply
ESP with 10 Days QPF
Ensemble:
2026-08-15
Issued:
2026-08-15
Hide Forecast
Forecast
Period
Forecasts Are in KAF
30 Year
Average
(1991-2020)
90 %
50 %
%
Average
10 %
APR-SEP
688
1040
96
1318
1082
APR-JUL
608
912
103
1197
881
APR-AUG
649
977
101
1260
969
JAN-SEP
1725
2333
99
2891
2363
JAN-JUL
1603
2187
101
2759
2162
OCT-SEP
2556
3281
96
4171
3417
Move the mouse over the desired "Forecast Period" to display a graph.
Max Scale
Scale To Data
Scale To Last 45 Days
Show Min/Max Ensemble Volume
Show Tooltips Help
Overlay
ESP10
Data Files
/chpsesp/ensemble/watersupply/MEWW1W_SQIN.ESPF10.csv
MEWW1W_SQIN.ESPF0.csv|2026-08-15
MEWW1W_SQIN.ESPF10.csv|2026-08-15
MEWW1W_SQIN.ESPFM.csv|2026-08-15
APR-SEP
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ESP10,ESPM,ESP0
ESP10,ESPM,ESP0
Last Forecast
