diff --git a/bin/weecfg/tests/expected/weewx43_user_expected.conf b/bin/weecfg/tests/expected/weewx43_user_expected.conf
index 23f8543e..66cd05f9 100644
--- a/bin/weecfg/tests/expected/weewx43_user_expected.conf
+++ b/bin/weecfg/tests/expected/weewx43_user_expected.conf
@@ -26,7 +26,7 @@ log_failure = True
 socket_timeout = 20
 
 # Do not modify this - it is used by setup.py when installing and updating.
-version = 4.8.0
+version = 4.9.0a1
 
 ##############################################################################
 
diff --git a/bin/weewx/__init__.py b/bin/weewx/__init__.py
index 6b20b9ca..385f23ba 100644
--- a/bin/weewx/__init__.py
+++ b/bin/weewx/__init__.py
@@ -7,7 +7,7 @@
 from __future__ import absolute_import
 import time
 
-__version__="4.8.0"
+__version__="4.9.0a1"
 
 # Holds the program launch time in unix epoch seconds:
 # Useful for calculating 'uptime.'
diff --git a/docs/customizing.htm b/docs/customizing.htm
index f9a29200..2b554802 100644
--- a/docs/customizing.htm
+++ b/docs/customizing.htm
@@ -44,7 +44,7 @@
         <div class="logoref">
             <a href='https://weewx.com'> <img src='images/logo-weewx.png' class='logo' style="float:right"
                                              alt="weewx logo"/> </a><br/> <span class='version'>
-Version: 4.8
+Version: 4.9
     </span>
         </div>
         <div class="title">WeeWX Customization Guide</div>
diff --git a/docs/devnotes.htm b/docs/devnotes.htm
index 7df0840f..5abc2e4d 100644
--- a/docs/devnotes.htm
+++ b/docs/devnotes.htm
@@ -47,7 +47,7 @@
         <div class="logoref">
             <a href='http://weewx.com'> <img src='images/logo-weewx.png' class='logo' style="float:right" alt="weewx logo"/>
             </a><br/> <span class='version'>
-Version: 4.8
+Version: 4.9
     </span>
         </div>
         <div class="title">Notes for Developers of the WeeWX Weather System</div>
diff --git a/docs/hardware.htm b/docs/hardware.htm
index 2a6a547f..8e5c270e 100644
--- a/docs/hardware.htm
+++ b/docs/hardware.htm
@@ -52,7 +52,7 @@
         <div class="logoref">
             <a href='https://weewx.com'> <img src='images/logo-weewx.png' class='logo' style="float:right" alt="weewx logo"/>
             </a><br/> <span class='version'>
-Version: 4.8
+Version: 4.9
     </span>
         </div>
         <div class="title">WeeWX Hardware Guide</div>
diff --git a/docs/readme.htm b/docs/readme.htm
index 77f5bc76..9afaae73 100644
--- a/docs/readme.htm
+++ b/docs/readme.htm
@@ -26,7 +26,7 @@
     <div class="logoref">
         <a href='https://weewx.com'> <img src='images/logo-weewx.png' class='logo' style="float:right" alt="weewx logo"/>
         </a><br/> <span class='version'>
-Version: 4.8
+Version: 4.9
     </span>
     </div>
     <div class="title">WeeWX Documentation</div>
diff --git a/docs/upgrading.htm b/docs/upgrading.htm
index 7b6f0726..d28220cb 100644
--- a/docs/upgrading.htm
+++ b/docs/upgrading.htm
@@ -80,7 +80,7 @@
         <div class="logoref">
             <a href='https://weewx.com'> <img src='images/logo-weewx.png' class='logo' style="float:right"
                                              alt="weewx logo"/> </a><br/> <span class='version'>
-Version: 4.8
+Version: 4.9
     </span>
         </div>
         <div class="title">WeeWX Upgrade Guide</div>
diff --git a/docs/usersguide.htm b/docs/usersguide.htm
index d08679a9..bfbe1b1e 100644
--- a/docs/usersguide.htm
+++ b/docs/usersguide.htm
@@ -47,7 +47,7 @@
         <div class="logoref">
             <a href='https://weewx.com'> <img src='images/logo-weewx.png' class='logo' style="float:right"
                                              alt="weewx logo"/> </a><br/> <span class='version'>
-Version: 4.8
+Version: 4.9
     </span>
         </div>
         <div class="title">User's Guide to WeeWX</div>
diff --git a/docs/utilities.htm b/docs/utilities.htm
index 245f87d7..5e3d4b62 100644
--- a/docs/utilities.htm
+++ b/docs/utilities.htm
@@ -49,7 +49,7 @@
         <div class="logoref">
             <a href='https://weewx.com'> <img src='images/logo-weewx.png' class='logo' style="float:right"
                                              alt="weewx logo"/> </a><br/> <span class='version'>
-Version: 4.8
+Version: 4.9
     </span>
         </div>
         <div class="title">WeeWX Utilities Guide</div>
diff --git a/setup.py b/setup.py
index fecd57ae..201cb429 100755
--- a/setup.py
+++ b/setup.py
@@ -32,7 +32,7 @@ from distutils.command.install_lib import install_lib
 from distutils.core import setup
 from distutils.debug import DEBUG
 
-VERSION = "4.8.0"
+VERSION = "4.9.0a1"
 
 if sys.version_info < (2, 7):
     log.fatal('WeeWX requires Python V2.7 or greater.')
diff --git a/skins/Ftp/skin.conf b/skins/Ftp/skin.conf
index 20cea48c..19a7f6c4 100644
--- a/skins/Ftp/skin.conf
+++ b/skins/Ftp/skin.conf
@@ -7,7 +7,7 @@
 ###############################################################################
 
 SKIN_NAME = Ftp
-SKIN_VERSION = 4.8.0
+SKIN_VERSION = 4.9.0a1
 
 [Generators]
     generator_list = weewx.reportengine.FtpGenerator
diff --git a/skins/Mobile/skin.conf b/skins/Mobile/skin.conf
index 90ec312b..75480615 100644
--- a/skins/Mobile/skin.conf
+++ b/skins/Mobile/skin.conf
@@ -1,7 +1,7 @@
 # configuration file for Mobile skin
 
 SKIN_NAME = Mobile
-SKIN_VERSION = 4.8.0
+SKIN_VERSION = 4.9.0a1
 
 [Extras]
     # Set this URL to display a radar image
diff --git a/skins/Rsync/skin.conf b/skins/Rsync/skin.conf
index 0df7bd09..bd7bd643 100644
--- a/skins/Rsync/skin.conf
+++ b/skins/Rsync/skin.conf
@@ -8,7 +8,7 @@
 ###############################################################################
 
 SKIN_NAME = Rsync
-SKIN_VERSION = 4.8.0
+SKIN_VERSION = 4.9.0a1
 
 [Generators]
     generator_list = weewx.reportengine.RsyncGenerator
diff --git a/skins/Seasons/skin.conf b/skins/Seasons/skin.conf
index dc848bec..0a9b313b 100644
--- a/skins/Seasons/skin.conf
+++ b/skins/Seasons/skin.conf
@@ -5,7 +5,7 @@
 ###############################################################################
 
 SKIN_NAME = Seasons
-SKIN_VERSION = 4.8.0
+SKIN_VERSION = 4.9.0a1
 
 ###############################################################################
 
diff --git a/skins/Smartphone/skin.conf b/skins/Smartphone/skin.conf
index e739ecbc..4aedfcb1 100644
--- a/skins/Smartphone/skin.conf
+++ b/skins/Smartphone/skin.conf
@@ -1,7 +1,7 @@
 # configuration file for Smartphone skin
 
 SKIN_NAME = Smartphone
-SKIN_VERSION = 4.8.0
+SKIN_VERSION = 4.9.0a1
 
 [Extras]
     # Set this URL to display a radar image
diff --git a/skins/Standard/skin.conf b/skins/Standard/skin.conf
index c48b9645..50584bf4 100644
--- a/skins/Standard/skin.conf
+++ b/skins/Standard/skin.conf
@@ -5,7 +5,7 @@
 ###############################################################################
 
 SKIN_NAME = Standard
-SKIN_VERSION = 4.8.0
+SKIN_VERSION = 4.9.0a1
 
 ###############################################################################
 
diff --git a/weewx.conf b/weewx.conf
index 12274ed6..00626619 100644
--- a/weewx.conf
+++ b/weewx.conf
@@ -20,7 +20,7 @@ log_success = True
 log_failure = True
 
 # Do not modify this. It is used when installing and updating weewx.
-version = 4.8.0
+version = 4.9.0a1
 
 ##############################################################################