diff --git a/parm/atm/obs/config/aircraft.yaml b/parm/atm/obs/config/aircraft.yaml
index 4920a90db..e0d292e26 100644
--- a/parm/atm/obs/config/aircraft.yaml
+++ b/parm/atm/obs/config/aircraft.yaml
@@ -3,7 +3,7 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)aircraft.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)aircraft.${{ current_cycle | to_YMDH }}.nc
     obsgrouping:
       group variables: ["stationIdentification"]
       sort variable: "pressure"
@@ -11,7 +11,7 @@ obs space:
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_aircraft_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_aircraft_${{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [windEastward, windNorthward, airTemperature, specificHumidity]
diff --git a/parm/atm/obs/config/amsua_n19.yaml b/parm/atm/obs/config/amsua_n19.yaml
index be40d9650..d866569b6 100644
--- a/parm/atm/obs/config/amsua_n19.yaml
+++ b/parm/atm/obs/config/amsua_n19.yaml
@@ -3,11 +3,11 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)amsua_n19.{{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)amsua_n19.{{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_amsua_n19_{{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_amsua_n19_{{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [brightnessTemperature]
@@ -22,8 +22,8 @@ obs operator:
     EndianType: little_endian
     CoefficientPath: $(DATA)/crtm/
 obs bias:
-  input file: $(DATA)/obs/$(GPREFIX)amsua_n19.satbias.nc4
-  output file: $(DATA)/bc/$(APREFIX)amsua_n19.satbias.nc4
+  input file: $(DATA)/obs/$(GPREFIX)amsua_n19.satbias.nc
+  output file: $(DATA)/bc/$(APREFIX)amsua_n19.satbias.nc
   variational bc:
     predictors:
     - name: constant
@@ -46,11 +46,11 @@ obs bias:
     step size: 1.0e-4
     largest analysis variance: 10000.0
     prior:
-      input file: $(DATA)/obs/$(GPREFIX)amsua_n19.satbias_cov.nc4
+      input file: $(DATA)/obs/$(GPREFIX)amsua_n19.satbias_cov.nc
       inflation:
         ratio: 1.1
         ratio for small dataset: 2.0
-    output file: $(DATA)/bc/$(APREFIX)amsua_n19.satbias_cov.nc4
+    output file: $(DATA)/bc/$(APREFIX)amsua_n19.satbias_cov.nc
 obs filters:
 - filter: BlackList
   filter variables:
diff --git a/parm/atm/obs/config/atms_n20.yaml b/parm/atm/obs/config/atms_n20.yaml
index 5cb9c27f3..d32ce2489 100644
--- a/parm/atm/obs/config/atms_n20.yaml
+++ b/parm/atm/obs/config/atms_n20.yaml
@@ -27,8 +27,8 @@ obs operator:
     Absorbers: [H2O, O3]
 
 obs bias:
-  input file: $(DATA)/obs/$(GPREFIX)atms_n20.satbias.nc4
-  output file: $(DATA)/bc/$(APREFIX)atms_n20.satbias.nc4
+  input file: $(DATA)/obs/$(GPREFIX)atms_n20.satbias.nc
+  output file: $(DATA)/bc/$(APREFIX)atms_n20.satbias.nc
   variational bc:
     predictors:
     - name: constant
@@ -51,11 +51,11 @@ obs bias:
     step size: 1.0e-4
     largest analysis variance: 10000.0
     prior:
-      input file: $(DATA)/obs/$(GPREFIX)atms_n20.satbias_cov.nc4
+      input file: $(DATA)/obs/$(GPREFIX)atms_n20.satbias_cov.nc
       inflation:
         ratio: 1.1
         ratio for small dataset: 2.0
-    output file: $(DATA)/bc/$(APREFIX)atms_n20.satbias_cov.nc4
+    output file: $(DATA)/bc/$(APREFIX)atms_n20.satbias_cov.nc
 
 obs pre filters:
 # Step 0-A: Create Diagnostic Flags
diff --git a/parm/atm/obs/config/atms_npp.yaml b/parm/atm/obs/config/atms_npp.yaml
index 0a9b633b6..30926fc20 100644
--- a/parm/atm/obs/config/atms_npp.yaml
+++ b/parm/atm/obs/config/atms_npp.yaml
@@ -27,8 +27,8 @@ obs operator:
     Absorbers: [H2O, O3]
 
 obs bias:
-  input file: $(DATA)/obs/$(GPREFIX)atms_npp.satbias.nc4
-  output file: $(DATA)/bc/$(APREFIX)atms_npp.satbias.nc4
+  input file: $(DATA)/obs/$(GPREFIX)atms_npp.satbias.nc
+  output file: $(DATA)/bc/$(APREFIX)atms_npp.satbias.nc
   variational bc:
     predictors:
     - name: constant
@@ -51,11 +51,11 @@ obs bias:
     step size: 1.0e-4
     largest analysis variance: 10000.0
     prior:
-      input file: $(DATA)/obs/$(GPREFIX)atms_npp.satbias_cov.nc4
+      input file: $(DATA)/obs/$(GPREFIX)atms_npp.satbias_cov.nc
       inflation:
         ratio: 1.1
         ratio for small dataset: 2.0
-    output file: $(DATA)/bc/$(APREFIX)atms_npp.satbias_cov.nc4
+    output file: $(DATA)/bc/$(APREFIX)atms_npp.satbias_cov.nc
 
 obs pre filters:
 # Step 0-A: Create Diagnostic Flags
diff --git a/parm/atm/obs/config/cris-fsr_n20.yaml b/parm/atm/obs/config/cris-fsr_n20.yaml
index 579439862..3b26fb672 100644
--- a/parm/atm/obs/config/cris-fsr_n20.yaml
+++ b/parm/atm/obs/config/cris-fsr_n20.yaml
@@ -3,11 +3,11 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)cris-fsr_n20.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)cris-fsr_n20.${{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_cris-fsr_n20_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_cris-fsr_n20_${{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [brightness_temperature]
@@ -53,8 +53,8 @@ obs operator:
     EndianType: little_endian
     CoefficientPath: $(DATA)/crtm/
 obs bias:
-  input file: $(DATA)/obs/$(GPREFIX)cris-fsr_n20.satbias.nc4
-  output file: $(DATA)/bc/$(APREFIX)cris-fsr_n20.satbias.nc4
+  input file: $(DATA)/obs/$(GPREFIX)cris-fsr_n20.satbias.nc
+  output file: $(DATA)/bc/$(APREFIX)cris-fsr_n20.satbias.nc
   variational bc:
     predictors:
     - name: constant
@@ -77,11 +77,11 @@ obs bias:
     step size: 1.0e-4
     largest analysis variance: 10000.0
     prior:
-      input file: $(DATA)/obs/$(GPREFIX)cris-fsr_n20.satbias_cov.nc4
+      input file: $(DATA)/obs/$(GPREFIX)cris-fsr_n20.satbias_cov.nc
       inflation:
         ratio: 1.1
         ratio for small dataset: 2.0
-    output file: $(DATA)/bc/$(APREFIX)cris-fsr_n20.satbias_cov.nc4
+    output file: $(DATA)/bc/$(APREFIX)cris-fsr_n20.satbias_cov.nc
 #
 #obs filters:
 ##  Wavenumber Check
diff --git a/parm/atm/obs/config/cris-fsr_npp.yaml b/parm/atm/obs/config/cris-fsr_npp.yaml
index 55409f454..ff0aabe86 100644
--- a/parm/atm/obs/config/cris-fsr_npp.yaml
+++ b/parm/atm/obs/config/cris-fsr_npp.yaml
@@ -3,11 +3,11 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)cris-fsr_npp.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)cris-fsr_npp.${{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_cris-fsr_npp_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_cris-fsr_npp_${{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [brightness_temperature]
@@ -53,8 +53,8 @@ obs operator:
     EndianType: little_endian
     CoefficientPath: $(DATA)/crtm/
 obs bias:
-  input file: $(DATA)/obs/$(GPREFIX)cris-fsr_npp.satbias.nc4
-  output file: $(DATA)/bc/$(APREFIX)cris-fsr_npp.satbias.nc4
+  input file: $(DATA)/obs/$(GPREFIX)cris-fsr_npp.satbias.nc
+  output file: $(DATA)/bc/$(APREFIX)cris-fsr_npp.satbias.nc
   variational bc:
     predictors:
     - name: constant
@@ -77,11 +77,11 @@ obs bias:
     step size: 1.0e-4
     largest analysis variance: 10000.0
     prior:
-      input file: $(DATA)/obs/$(GPREFIX)cris-fsr_npp.satbias_cov.nc4
+      input file: $(DATA)/obs/$(GPREFIX)cris-fsr_npp.satbias_cov.nc
       inflation:
         ratio: 1.1
         ratio for small dataset: 2.0
-    output file: $(DATA)/bc/$(APREFIX)cris-fsr_npp.satbias_cov.nc4
+    output file: $(DATA)/bc/$(APREFIX)cris-fsr_npp.satbias_cov.nc
 #obs filters:
 ##  Wavenumber Check
 #- filter: BlackList
diff --git a/parm/atm/obs/config/gnssro.yaml b/parm/atm/obs/config/gnssro.yaml
index 949a4f87b..1b4d1a0dd 100644
--- a/parm/atm/obs/config/gnssro.yaml
+++ b/parm/atm/obs/config/gnssro.yaml
@@ -18,7 +18,7 @@ obs space:
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_gnssro_{{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_gnssro_{{ current_cycle | to_YMDH }}.nc
   simulated variables: [bendingAngle]
 
 obs filters:
diff --git a/parm/atm/obs/config/iasi_metop-a.yaml b/parm/atm/obs/config/iasi_metop-a.yaml
index f5c7a602a..fdc974d8e 100644
--- a/parm/atm/obs/config/iasi_metop-a.yaml
+++ b/parm/atm/obs/config/iasi_metop-a.yaml
@@ -74,8 +74,8 @@ obs operator:
     Absorbers: [H2O,O3]
 
 obs bias:
-  input file: $(DATA)/obs/$(GPREFIX)iasi_metop-a.satbias.nc4
-  output file: $(DATA)/bc/$(APREFIX)iasi_metop-a.satbias.nc4
+  input file: $(DATA)/obs/$(GPREFIX)iasi_metop-a.satbias.nc
+  output file: $(DATA)/bc/$(APREFIX)iasi_metop-a.satbias.nc
   variational bc:
     predictors:
     - name: constant
@@ -98,11 +98,11 @@ obs bias:
     step size: 1.0e-4
     largest analysis variance: 10000.0
     prior:
-      input file: $(DATA)/obs/$(GPREFIX)iasi_metop-a.satbias_cov.nc4
+      input file: $(DATA)/obs/$(GPREFIX)iasi_metop-a.satbias_cov.nc
       inflation:
         ratio: 1.1
         ratio for small dataset: 2.0
-    output file: $(DATA)/bc/$(APREFIX)iasi_metop-a.satbias_cov.nc4
+    output file: $(DATA)/bc/$(APREFIX)iasi_metop-a.satbias_cov.nc
 
 obs pre filters:
 # Step 0-A: Create Diagnostic Flags
diff --git a/parm/atm/obs/config/iasi_metop-b.yaml b/parm/atm/obs/config/iasi_metop-b.yaml
index 1a4681dc6..2f8f1424e 100644
--- a/parm/atm/obs/config/iasi_metop-b.yaml
+++ b/parm/atm/obs/config/iasi_metop-b.yaml
@@ -74,8 +74,8 @@ obs operator:
     Absorbers: [H2O,O3]
 
 obs bias:
-  input file: $(DATA)/obs/$(GPREFIX)iasi_metop-b.satbias.nc4
-  output file: $(DATA)/bc/$(APREFIX)iasi_metop-b.satbias.nc4
+  input file: $(DATA)/obs/$(GPREFIX)iasi_metop-b.satbias.nc
+  output file: $(DATA)/bc/$(APREFIX)iasi_metop-b.satbias.nc
   variational bc:
     predictors:
     - name: constant
@@ -98,11 +98,11 @@ obs bias:
     step size: 1.0e-4
     largest analysis variance: 10000.0
     prior:
-      input file: $(DATA)/obs/$(GPREFIX)iasi_metop-b.satbias_cov.nc4
+      input file: $(DATA)/obs/$(GPREFIX)iasi_metop-b.satbias_cov.nc
       inflation:
         ratio: 1.1
         ratio for small dataset: 2.0
-    output file: $(DATA)/bc/$(APREFIX)iasi_metop-b.satbias_cov.nc4
+    output file: $(DATA)/bc/$(APREFIX)iasi_metop-b.satbias_cov.nc
 
 obs pre filters:
 # Step 0-A: Create Diagnostic Flags
diff --git a/parm/atm/obs/config/lgetkf_amsua_n19.yaml b/parm/atm/obs/config/lgetkf_amsua_n19.yaml
index d5fe9691a..a29cb8bdf 100644
--- a/parm/atm/obs/config/lgetkf_amsua_n19.yaml
+++ b/parm/atm/obs/config/lgetkf_amsua_n19.yaml
@@ -6,11 +6,11 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: ./obs/$(OPREFIX)amsua_n19.{{ current_cycle | to_YMDH }}.nc4
+      obsfile: ./obs/$(OPREFIX)amsua_n19.{{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: ./diags/diag_amsua_n19_{{ current_cycle | to_YMDH }}.nc4
+      obsfile: ./diags/diag_amsua_n19_{{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [brightnessTemperature]
@@ -27,8 +27,8 @@ obs operator:
 obs error:
   covariance model: diagonal
 obs bias:
-  input file: $(DATA)/obs/$(GPREFIX)amsua_n19.satbias.nc4
-  output file: $(DATA)/bc/$(APREFIX)amsua_n19.satbias.nc4
+  input file: $(DATA)/obs/$(GPREFIX)amsua_n19.satbias.nc
+  output file: $(DATA)/bc/$(APREFIX)amsua_n19.satbias.nc
   variational bc:
     predictors:
     - name: constant
@@ -51,11 +51,11 @@ obs bias:
     step size: 1.0e-4
     largest analysis variance: 10000.0
     prior:
-      input file: $(DATA)/obs/$(GPREFIX)amsua_n19.satbias_cov.nc4
+      input file: $(DATA)/obs/$(GPREFIX)amsua_n19.satbias_cov.nc
       inflation:
         ratio: 1.1
         ratio for small dataset: 2.0
-    output file: $(DATA)/bc/$(APREFIX)amsua_n19.satbias_cov.nc4
+    output file: $(DATA)/bc/$(APREFIX)amsua_n19.satbias_cov.nc
 obs filters:
 - filter: Bounds Check
   filter variables:
diff --git a/parm/atm/obs/config/lgetkf_sondes.yaml b/parm/atm/obs/config/lgetkf_sondes.yaml
index 4f2358097..8515508a6 100644
--- a/parm/atm/obs/config/lgetkf_sondes.yaml
+++ b/parm/atm/obs/config/lgetkf_sondes.yaml
@@ -6,11 +6,11 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: ./obs/$(OPREFIX)sondes.{{ current_cycle | to_YMDH }}.nc4
+      obsfile: ./obs/$(OPREFIX)sondes.{{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: ./diags/diag_sondes_lgetkf_{{ current_cycle | to_YMDH }}.nc4
+      obsfile: ./diags/diag_sondes_lgetkf_{{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [windEastward, windNorthward, airTemperature]
diff --git a/parm/atm/obs/config/omi_aura.yaml b/parm/atm/obs/config/omi_aura.yaml
index 20cabced5..27fa97004 100644
--- a/parm/atm/obs/config/omi_aura.yaml
+++ b/parm/atm/obs/config/omi_aura.yaml
@@ -3,11 +3,11 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)omi_aura.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)omi_aura.${{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_omi_aura_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_omi_aura_${{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [ozoneTotal]
diff --git a/parm/atm/obs/config/ompsnp_npp.yaml b/parm/atm/obs/config/ompsnp_npp.yaml
index c18b9abed..f543a693d 100644
--- a/parm/atm/obs/config/ompsnp_npp.yaml
+++ b/parm/atm/obs/config/ompsnp_npp.yaml
@@ -3,7 +3,7 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)ompsnp_npp.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)ompsnp_npp.${{ current_cycle | to_YMDH }}.nc
     obsgrouping:
       group variables: ["latitude"]
       sort variable: "pressure"
@@ -11,7 +11,7 @@ obs space:
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_ompsnp_npp_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_ompsnp_npp_${{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [ozoneLayer]
diff --git a/parm/atm/obs/config/ompstc8_npp.yaml b/parm/atm/obs/config/ompstc8_npp.yaml
index 545983d93..1563c4534 100644
--- a/parm/atm/obs/config/ompstc8_npp.yaml
+++ b/parm/atm/obs/config/ompstc8_npp.yaml
@@ -3,11 +3,11 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)ompstc8_npp.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)ompstc8_npp.${{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_ompstc8_npp_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_ompstc8_npp_${{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [ozoneTotal]
diff --git a/parm/atm/obs/config/satwind.yaml b/parm/atm/obs/config/satwind.yaml
index 853cbce77..80b74e23c 100644
--- a/parm/atm/obs/config/satwind.yaml
+++ b/parm/atm/obs/config/satwind.yaml
@@ -3,11 +3,11 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)satwind.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)satwind.${{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_satwind_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_satwind_${{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [windEastward, windNorthward]
diff --git a/parm/atm/obs/config/satwind_ahi_h8.yaml b/parm/atm/obs/config/satwind_ahi_h8.yaml
index c66afaa67..2cfc17e02 100644
--- a/parm/atm/obs/config/satwind_ahi_h8.yaml
+++ b/parm/atm/obs/config/satwind_ahi_h8.yaml
@@ -7,7 +7,7 @@ obs space:
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_satwind_ahi_h8_{{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_satwind_ahi_h8_{{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [windEastward, windNorthward]
diff --git a/parm/atm/obs/config/sfc.yaml b/parm/atm/obs/config/sfc.yaml
index 31fd74c0c..b846e98f0 100644
--- a/parm/atm/obs/config/sfc.yaml
+++ b/parm/atm/obs/config/sfc.yaml
@@ -3,11 +3,11 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)sfc.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)sfc.${{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_sfc_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_sfc_${{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [stationPressure]
diff --git a/parm/atm/obs/config/sfcship.yaml b/parm/atm/obs/config/sfcship.yaml
index c3530f404..b9f548b53 100644
--- a/parm/atm/obs/config/sfcship.yaml
+++ b/parm/atm/obs/config/sfcship.yaml
@@ -3,12 +3,12 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)sfcship.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)sfcship.${{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
       overwrite: true
-      obsfile: $(DATA)/diags/diag_sfcship_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_sfcship_${{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [stationPressure, airTemperature, specificHumidity]
diff --git a/parm/atm/obs/config/sondes.yaml b/parm/atm/obs/config/sondes.yaml
index e9331f7bd..5c83686eb 100644
--- a/parm/atm/obs/config/sondes.yaml
+++ b/parm/atm/obs/config/sondes.yaml
@@ -3,7 +3,7 @@ obs space:
   obsdatain:
     engine: 
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)sondes.{{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)sondes.{{ current_cycle | to_YMDH }}.nc
     obsgrouping:
       group variables: ["stationIdentification"]
       sort variable: "pressure"
@@ -11,7 +11,7 @@ obs space:
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_sondes_{{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_sondes_{{ current_cycle | to_YMDH }}.nc
   io pool:
     max pool size: 1
   simulated variables: [stationPressure, airTemperature, windEastward, windNorthward, specificHumidity]
diff --git a/parm/atm/obs/config/ssmis_f17.yaml b/parm/atm/obs/config/ssmis_f17.yaml
index 5054951ef..dc16f1581 100644
--- a/parm/atm/obs/config/ssmis_f17.yaml
+++ b/parm/atm/obs/config/ssmis_f17.yaml
@@ -10,16 +10,16 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)ssmis_f17.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)ssmis_f17.${{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_ssmis_f17_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_ssmis_f17_${{ current_cycle | to_YMDH }}.nc
   simulated variables: [brightness_temperature]
   channels: 1-24
 obs bias:
-  input file: $(DATA)/obs/$(GPREFIX)ssmis_f17.satbias.nc4
-  output file: $(DATA)/bc/$(APREFIX)ssmis_f17.satbias.nc4
+  input file: $(DATA)/obs/$(GPREFIX)ssmis_f17.satbias.nc
+  output file: $(DATA)/bc/$(APREFIX)ssmis_f17.satbias.nc
   variational bc:
     predictors:
     - name: constant
diff --git a/parm/atm/obs/config/ssmis_f18.yaml b/parm/atm/obs/config/ssmis_f18.yaml
index 2c757268a..c22598815 100644
--- a/parm/atm/obs/config/ssmis_f18.yaml
+++ b/parm/atm/obs/config/ssmis_f18.yaml
@@ -10,16 +10,16 @@ obs space:
   obsdatain:
     engine:
       type: H5File
-      obsfile: $(DATA)/obs/$(OPREFIX)ssmis_f18.${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/obs/$(OPREFIX)ssmis_f18.${{ current_cycle | to_YMDH }}.nc
   obsdataout:
     engine:
       type: H5File
-      obsfile: $(DATA)/diags/diag_ssmis_f18_${{ current_cycle | to_YMDH }}.nc4
+      obsfile: $(DATA)/diags/diag_ssmis_f18_${{ current_cycle | to_YMDH }}.nc
   simulated variables: [brightness_temperature]
   channels: 1-24
 obs bias:
-  input file: $(DATA)/obs/$(GPREFIX)ssmis_f18.satbias.nc4
-  output file: $(DATA)/bc/$(APREFIX)ssmis_f18.satbias.nc4
+  input file: $(DATA)/obs/$(GPREFIX)ssmis_f18.satbias.nc
+  output file: $(DATA)/bc/$(APREFIX)ssmis_f18.satbias.nc
   variational bc:
     predictors:
     - name: constant